Kiểm tra xem chuỗi có ký tự lặp lại không javascript
Nếu bạn kiểm tra số lần xuất hiện của 'o' trong chuỗi 'school', kết quả là 2 Show
ví dụ 1. Kiểm tra sự xuất hiện của một ký tự bằng vòng lặp
đầu ra Enter a string: school Enter a letter to check: o 2 Trong ví dụ trên, người dùng được nhắc nhập một chuỗi và ký tự để kiểm tra
ví dụ 2. Kiểm tra sự xuất hiện của một ký tự bằng Regex
đầu ra Enter a string: school Enter a letter to check: o 2 Trong ví dụ trên, một biểu thức chính quy (regex) được sử dụng để tìm sự xuất hiện của một chuỗi
Giải pháp đơn giản sử dụng độ phức tạp O(N^2). Giải pháp là lặp qua chuỗi cho từng ký tự và tìm kiếm tương tự trong phần còn lại của chuỗi. Điều này sẽ cần hai vòng lặp và do đó không tối ưu. Thực hiện C++Enter a string: school Enter a letter to check: o 2617 Enter a string: school Enter a letter to check: o 2618 Enter a string: school Enter a letter to check: o 2619 Enter a string: school Enter a letter to check: o 2620
Enter a string: school Enter a letter to check: o 2621 g0 g1 g2 g3 g4 g5 g6 g7 g8 g7 g2 g1 g7 g3 g4____45 g6 g7 g6 g9 g3 g1____45 g3 g9 g6 g6 g7 g8 g6 g6 Enter a string: school Enter a letter to check: o 251 Enter a string: school Enter a letter to check: o 252 ________ 351 ________ 354 ________ 355 _______46____357 g9 Enter a string: school Enter a letter to check: o 257 g9 g7 Enter a string: school Enter a letter to check: o 26172 ________ 46 ________ 354 ________ 355 g7 Enter a string: school Enter a letter to check: o 257
g7 Enter a string: school Enter a letter to check: o 26179 Enter a string: school Enter a letter to check: o 26180 Enter a string: school Enter a letter to check: o 257
Enter a string: school Enter a letter to check: o 26182 g2 Enter a string: school Enter a letter to check: o 26184 g6 g7 g4 Enter a string: school Enter a letter to check: o 26188 Enter a string: school Enter a letter to check: o 26189 Enter a string: school Enter a letter to check: o 255 g7 g2 Enter a string: school Enter a letter to check: o 26193 g7 g7 Enter a string: school Enter a letter to check: o 26196 g9 Enter a string: school Enter a letter to check: o 26198 Enter a string: school Enter a letter to check: o 26199 Enter a string: school Enter a letter to check: o 255 _______47____16202 g9 Enter a string: school Enter a letter to check: o 26204 g7 Enter a string: school Enter a letter to check: o 26179 Enter a string: school Enter a letter to check: o 26207 Enter a string: school Enter a letter to check: o 257
Enter a string: school Enter a letter to check: o 26209 Enter a string: school Enter a letter to check: o 26210 CEnter a string: school Enter a letter to check: o 26211 Enter a string: school Enter a letter to check: o 26212 Enter a string: school Enter a letter to check: o 26213 Enter a string: school Enter a letter to check: o 2620
g2 g3 g4 g5 g6 g7 g8 g7 g2 g1 g7 g3 g4____45 g09 g9 g3 g1____45 g14 g6 g7 g17 Enter a string: school Enter a letter to check: o 251 Enter a string: school Enter a letter to check: o 252 ________ 351 ________ 354 ________ 355 _______46____357 g9 Enter a string: school Enter a letter to check: o 257 g9 g7 Enter a string: school Enter a letter to check: o 26172 ________ 46 ________ 354 ________ 355 g7 Enter a string: school Enter a letter to check: o 257
g7 Enter a string: school Enter a letter to check: o 26179 Enter a string: school Enter a letter to check: o 26180 Enter a string: school Enter a letter to check: o 257
Enter a string: school Enter a letter to check: o 26182 g2 Enter a string: school Enter a letter to check: o 26184 g6 g7 g4 Enter a string: school Enter a letter to check: o 26188 Enter a string: school Enter a letter to check: o 26189 Enter a string: school Enter a letter to check: o 255 g7 g2 Enter a string: school Enter a letter to check: o 26193 g7 g7 Enter a string: school Enter a letter to check: o 26196 g9____455____456 Enter a string: school Enter a letter to check: o 26199 g58 _______47____16202 g9 g55____456 g64 g65 g7 Enter a string: school Enter a letter to check: o 26179 Enter a string: school Enter a letter to check: o 26207 Enter a string: school Enter a letter to check: o 257 Javag70 g71 g72 g73 g72 g75
g76 g77
g7 g79 g2 g81 g7 g6 g9 g9 g8 g9 g2 g89 g90 g91 g9 g3 ________ 494 g95 ________ 496 g9 g6 g6 g3 g01____490 g03 g6 g6 Enter a string: school Enter a letter to check: o 251 g7 g08 Enter a string: school Enter a letter to check: o 251 g6 _______411____352 ________ 411 ________ 354 ________ 355 Enter a string: school Enter a letter to check: o 251 Enter a string: school Enter a letter to check: o 257 _______46____357 g6 g7 g22____490 g24 ________ 351 ________ 354 ________ 355 g9 Enter a string: school Enter a letter to check: o 257 g7 g9 Enter a string: school Enter a letter to check: o 26179 Enter a string: school Enter a letter to check: o 26180 g7 Enter a string: school Enter a letter to check: o 257 g7 _______47____16182 g7 g79 g41 g42 g43 g7 g6 g9 g47 Enter a string: school Enter a letter to check: o 26189 Enter a string: school Enter a letter to check: o 255 g9 g2 Enter a string: school Enter a letter to check: o 26193 g9 g9 g7 g56____490 g24 _______46____460____16199 g58 _______49____16202 g9 g66 g7 Enter a string: school Enter a letter to check: o 257 Enter a string: school Enter a letter to check: o 257
g70 Python3g71 g72
g73 g74
g7 g76 g7 g78 g79 g80 g90 g7 g3 g84 g85 g86 g56 g88 g89 g7 g9 g3 g93 g85 g86 g96 g97 g90 g99 g88 g89 g9 g6 g7 g05____479 g79 g08 Enter a string: school Enter a letter to check: o 251 g78 g79 g84 Enter a string: school Enter a letter to check: o 251 Enter a string: school Enter a letter to check: o 254 g6 g9 g7 g18 g79 g80 g90 g22 _______46____354
g7 Enter a string: school Enter a letter to check: o 26179 g78
g28 g7 g30 g79 g79 g33 g34
g7 g36 g79 Enter a string: school Enter a letter to check: o 26189 g7 g40 g79 g3____436 g24 g7 g7 g47 g79 g79 g80 g90 g22 g9 g54 g56____16199 g24 _______47____16202____434 g9 g54 g56______436 g65 g7 g67 g68 C#g69 g71 Enter a string: school Enter a letter to check: o 2621 g72
g76 g77
g7 g79 g2 g3 g79 g80 g7 g6 g9 g9 g8 g9 g2 g1 ________ 49 ________ 43 ________ 491 g9 g6 g6 g3 g96 g6 g6 Enter a string: school Enter a letter to check: o 251 g7 g8 Enter a string: school Enter a letter to check: o 251 g6 _______411____352 ________ 411 ________ 354 ________ 355 Enter a string: school Enter a letter to check: o 251 Enter a string: school Enter a letter to check: o 257 _______46____357 g6 g7 Enter a string: school Enter a letter to check: o 26172 ________ 351 ________ 354 ________ 355 g9 Enter a string: school Enter a letter to check: o 257 g7 g9 Enter a string: school Enter a letter to check: o 26179 Enter a string: school Enter a letter to check: o 26180 g7 Enter a string: school Enter a letter to check: o 257 g7 _______47____16182 g7 g79 g41 g42 Enter a string: school Enter a letter to check: o 2534 g7 g6 g9 g79 Enter a string: school Enter a letter to check: o 2539____16189 Enter a string: school Enter a letter to check: o 255 g9 g2 Enter a string: school Enter a letter to check: o 26193 g9 g9 g7 Enter a string: school Enter a letter to check: o 26196 _______46____3550____16199 g58 _______49____16202 g9____3556 g7 Enter a string: school Enter a letter to check: o 257 Enter a string: school Enter a letter to check: o 257
g70 PHPEnter a string: school Enter a letter to check: o 2561 Enter a string: school Enter a letter to check: o 2562 Enter a string: school Enter a letter to check: o 2618
Enter a string: school Enter a letter to check: o 2564 g3____3566____424 g6 g7 g8 g7____3572 Enter a string: school Enter a letter to check: o 2573 g7 g3 g56_______3577 Enter a string: school Enter a letter to check: o 2578 Enter a string: school Enter a letter to check: o 2577 Enter a string: school Enter a letter to check: o 2580 g5 g56____3566 g58 Enter a string: school Enter a letter to check: o 2577 Enter a string: school Enter a letter to check: o 2586 g7 g6 g9 g3 g56______3592 Enter a string: school Enter a letter to check: o 2593 Enter a string: school Enter a letter to check: o 2577 Enter a string: school Enter a letter to check: o 2595 Enter a string: school Enter a letter to check: o 2596 Enter a string: school Enter a letter to check: o 2592 Enter a string: school Enter a letter to check: o 2580 g5 g56 Enter a string: school Enter a letter to check: o 2566 g58 Enter a string: school Enter a letter to check: o 2592 Enter a string: school Enter a letter to check: o 2586 g9 g6 g6 g7 g56_______3566 Enter a string: school Enter a letter to check: o 261711 Enter a string: school Enter a letter to check: o 2577 Enter a string: school Enter a letter to check: o 261713 Enter a string: school Enter a letter to check: o 2566 Enter a string: school Enter a letter to check: o 261711 Enter a string: school Enter a letter to check: o 2592 Enter a string: school Enter a letter to check: o 261717 g6 g6 Enter a string: school Enter a letter to check: o 251____3572 g79 Enter a string: school Enter a letter to check: o 2577 Enter a string: school Enter a letter to check: o 255 ________ 351 ________ 354 ________ 355 _______46____357 g9 Enter a string: school Enter a letter to check: o 257 g9 g7 g56______3572 Enter a string: school Enter a letter to check: o 261736 ________ 46 ________ 354 ________ 355 g7 Enter a string: school Enter a letter to check: o 257
g7 Enter a string: school Enter a letter to check: o 26179 Enter a string: school Enter a letter to check: o 2572 Enter a string: school Enter a letter to check: o 255 Enter a string: school Enter a letter to check: o 257
Enter a string: school Enter a letter to check: o 26182 Enter a string: school Enter a letter to check: o 261748 g79 Enter a string: school Enter a letter to check: o 26189 Enter a string: school Enter a letter to check: o 255 Enter a string: school Enter a letter to check: o 261752 Enter a string: school Enter a letter to check: o 261753____161748 g58
g7 g56____161752 Enter a string: school Enter a letter to check: o 261759 g7 Enter a string: school Enter a letter to check: o 261761 g56 Enter a string: school Enter a letter to check: o 26199 g58 Enter a string: school Enter a letter to check: o 26202 g7 Enter a string: school Enter a letter to check: o 261761 g56 Enter a string: school Enter a letter to check: o 261748 Enter a string: school Enter a letter to check: o 261711 Enter a string: school Enter a letter to check: o 261752 Enter a string: school Enter a letter to check: o 261772
Enter a string: school Enter a letter to check: o 261773 Enter a string: school Enter a letter to check: o 261774 JavascriptEnter a string: school Enter a letter to check: o 261775
Enter a string: school Enter a letter to check: o 261776 Enter a string: school Enter a letter to check: o 2618 Enter a string: school Enter a letter to check: o 2564 Enter a string: school Enter a letter to check: o 261779 g6 g7 _______47____161783 _______47____161785 _______47____43____161788 g7 g6 g9____43____161793 g9 g6 g6 g7 g8 g6 g6 Enter a string: school Enter a letter to check: o 251 Enter a string: school Enter a letter to check: o 252 ________ 351 ________ 354 ________ 355 _______46____357 g9 Enter a string: school Enter a letter to check: o 257 g9 g7 Enter a string: school Enter a letter to check: o 26172 ________ 46 ________ 354 ________ 355 g7 Enter a string: school Enter a letter to check: o 257 g7 Enter a string: school Enter a letter to check: o 26179 Enter a string: school Enter a letter to check: o 26180 Enter a string: school Enter a letter to check: o 257
Enter a string: school Enter a letter to check: o 26182 Enter a string: school Enter a letter to check: o 261823 Enter a string: school Enter a letter to check: o 26189 Enter a string: school Enter a letter to check: o 255 Enter a string: school Enter a letter to check: o 261826
g7 Enter a string: school Enter a letter to check: o 26196 g7 Enter a string: school Enter a letter to check: o 261830 Enter a string: school Enter a letter to check: o 26199 g58 Enter a string: school Enter a letter to check: o 26202 _______47____161835 g7 Enter a string: school Enter a letter to check: o 261837
Enter a string: school Enter a letter to check: o 261838 Đầu ra g Tối ưu hóa bằng cách đếm số lần xuất hiện Giải pháp này được tối ưu hóa bằng cách sử dụng các kỹ thuật sau.
Thực hiện C++Enter a string: school Enter a letter to check: o 261839 Enter a string: school Enter a letter to check: o 26212 Enter a string: school Enter a letter to check: o 261841
Enter a string: school Enter a letter to check: o 2621 g0 g1 Enter a string: school Enter a letter to check: o 261845 Enter a string: school Enter a letter to check: o 261846 Enter a string: school Enter a letter to check: o 261847
g2 Enter a string: school Enter a letter to check: o 261849 g4 g5 g6 g7 Enter a string: school Enter a letter to check: o 261854 g7 g2 Enter a string: school Enter a letter to check: o 261857
_______47____161859 g7____161861 g7 g2 Enter a string: school Enter a letter to check: o 261864
_______47____161866 g7 g2 Enter a string: school Enter a letter to check: o 261869
g7 g3 g4____45 g09 g9 Enter a string: school Enter a letter to check: o 261876 g2 Enter a string: school Enter a letter to check: o 261878 g9 g7 Enter a string: school Enter a letter to check: o 261881 g6 Enter a string: school Enter a letter to check: o 261883 g6 Enter a string: school Enter a letter to check: o 261885 g9 Enter a string: school Enter a letter to check: o 257____16202 g7 Enter a string: school Enter a letter to check: o 261890 g6 Enter a string: school Enter a letter to check: o 261883 g7 Enter a string: school Enter a letter to check: o 257
g7 g3 Enter a string: school Enter a letter to check: o 261897 g9 g7 Enter a string: school Enter a letter to check: o 261900 g6 g7 Enter a string: school Enter a letter to check: o 261903 Enter a string: school Enter a letter to check: o 261904 Enter a string: school Enter a letter to check: o 251 Enter a string: school Enter a letter to check: o 261906 g6 Enter a string: school Enter a letter to check: o 26202 g7 Enter a string: school Enter a letter to check: o 261910 Enter a string: school Enter a letter to check: o 251 Enter a string: school Enter a letter to check: o 261906 g9 Enter a string: school Enter a letter to check: o 257 g7 Enter a string: school Enter a letter to check: o 257
g7 Enter a string: school Enter a letter to check: o 26179 Enter a string: school Enter a letter to check: o 26180 Enter a string: school Enter a letter to check: o 257
Enter a string: school Enter a letter to check: o 26182 g2 Enter a string: school Enter a letter to check: o 26184 g6 g7 g4 Enter a string: school Enter a letter to check: o 26188 Enter a string: school Enter a letter to check: o 26189 Enter a string: school Enter a letter to check: o 255 g7 g2 Enter a string: school Enter a letter to check: o 261932 g7 g7 Enter a string: school Enter a letter to check: o 26196 g9 Enter a string: school Enter a letter to check: o 26198 Enter a string: school Enter a letter to check: o 26199 Enter a string: school Enter a letter to check: o 255 _______47____16202 g9 Enter a string: school Enter a letter to check: o 26204 g7 Enter a string: school Enter a letter to check: o 26179 Enter a string: school Enter a letter to check: o 26207 Enter a string: school Enter a letter to check: o 257
Enter a string: school Enter a letter to check: o 26209 Enter a string: school Enter a letter to check: o 26210 CEnter a string: school Enter a letter to check: o 26211 Enter a string: school Enter a letter to check: o 26212 Enter a string: school Enter a letter to check: o 26213 Enter a string: school Enter a letter to check: o 2620
Enter a string: school Enter a letter to check: o 261845 Enter a string: school Enter a letter to check: o 261846 Enter a string: school Enter a letter to check: o 261847
g2 Enter a string: school Enter a letter to check: o 261849 g4 g5 g6 g7 Enter a string: school Enter a letter to check: o 261854 g7 g2 Enter a string: school Enter a letter to check: o 261857
_______47____161859 g7____161861 g7 g2 Enter a string: school Enter a letter to check: o 261864
_______47____161866 g7 g2 Enter a string: school Enter a letter to check: o 261869
g7 g3 g4____45 g09 g9 Enter a string: school Enter a letter to check: o 261876 g2 Enter a string: school Enter a letter to check: o 261878 g9 g7 Enter a string: school Enter a letter to check: o 261881 g6 Enter a string: school Enter a letter to check: o 261883 g6 Enter a string: school Enter a letter to check: o 261885 g9 Enter a string: school Enter a letter to check: o 257____16202 g7 Enter a string: school Enter a letter to check: o 261890 g6 Enter a string: school Enter a letter to check: o 261883 g7 Enter a string: school Enter a letter to check: o 257
g7 g3 Enter a string: school Enter a letter to check: o 261897 g9 g7 Enter a string: school Enter a letter to check: o 261900 g6 g7 Enter a string: school Enter a letter to check: o 261903 Enter a string: school Enter a letter to check: o 261904 Enter a string: school Enter a letter to check: o 251 Enter a string: school Enter a letter to check: o 261906 g6 Enter a string: school Enter a letter to check: o 26202 g7 Enter a string: school Enter a letter to check: o 261910 Enter a string: school Enter a letter to check: o 251 Enter a string: school Enter a letter to check: o 261906 g9 Enter a string: school Enter a letter to check: o 257 g7 Enter a string: school Enter a letter to check: o 257
g7 Enter a string: school Enter a letter to check: o 26179 Enter a string: school Enter a letter to check: o 26180 Enter a string: school Enter a letter to check: o 257
Enter a string: school Enter a letter to check: o 26182 g2 Enter a string: school Enter a letter to check: o 26184 g6 g7 g4 Enter a string: school Enter a letter to check: o 26188 Enter a string: school Enter a letter to check: o 26189 Enter a string: school Enter a letter to check: o 255 g7 g2 Enter a string: school Enter a letter to check: o 261932 g7 g7 Enter a string: school Enter a letter to check: o 26196 g9____455____456 Enter a string: school Enter a letter to check: o 26199 g58 _______47____16202 g9 g55____456 g64 g65 g7 Enter a string: school Enter a letter to check: o 26179 Enter a string: school Enter a letter to check: o 26207 Enter a string: school Enter a letter to check: o 257 JavaEnter a string: school Enter a letter to check: o 262061 g71
g72 g75 g72 Enter a string: school Enter a letter to check: o 262066
g41 g76 Enter a string: school Enter a letter to check: o 262069 g6 g7 g41 g79 g2 Enter a string: school Enter a letter to check: o 262075 g7 g6 g9 Enter a string: school Enter a letter to check: o 261854 g9 g2 g89____490 Enter a string: school Enter a letter to check: o 262084
g9 Enter a string: school Enter a letter to check: o 261859 g9____161861 g9 g2 Enter a string: school Enter a letter to check: o 262091 Enter a string: school Enter a letter to check: o 262092 Enter a string: school Enter a letter to check: o 255 g9 g2 Enter a string: school Enter a letter to check: o 262096 Enter a string: school Enter a letter to check: o 262097 g2 Enter a string: school Enter a letter to check: o 262099
g9____161866 g9 g2 Enter a string: school Enter a letter to check: o 262104 Enter a string: school Enter a letter to check: o 262097 g2 Enter a string: school Enter a letter to check: o 262099
g9 g3 ________ 494 g95 ________ 496 g9 g6 g6 Enter a string: school Enter a letter to check: o 261876 g2 Enter a string: school Enter a letter to check: o 262118 g6 g7 Enter a string: school Enter a letter to check: o 262121______495 g24 g6 g6 Enter a string: school Enter a letter to check: o 251____161883 Enter a string: school Enter a letter to check: o 251 Enter a string: school Enter a letter to check: o 261885 _______46____357 g6 Enter a string: school Enter a letter to check: o 26202 g7 Enter a string: school Enter a letter to check: o 262121 g90 g24 Enter a string: school Enter a letter to check: o 251____161883 g9 Enter a string: school Enter a letter to check: o 257
g9 g3 ________ 494 g95 ________ 162146 g9 g6 g6 g7 Enter a string: school Enter a letter to check: o 262151____162152 g24 g6 g6 Enter a string: school Enter a letter to check: o 251 g7 Enter a string: school Enter a letter to check: o 262158____490 g24 Enter a string: school Enter a letter to check: o 261904 g11 Enter a string: school Enter a letter to check: o 261906 Enter a string: school Enter a letter to check: o 251 Enter a string: school Enter a letter to check: o 26202 g7 Enter a string: school Enter a letter to check: o 261910 g11 Enter a string: school Enter a letter to check: o 261906 _______46____357 g9 Enter a string: school Enter a letter to check: o 257
g9 Enter a string: school Enter a letter to check: o 26179 Enter a string: school Enter a letter to check: o 26180 g7 Enter a string: school Enter a letter to check: o 257
Enter a string: school Enter a letter to check: o 26182 g7 g41 g79 g42 Enter a string: school Enter a letter to check: o 262184 g7 g6 g9 g47 Enter a string: school Enter a letter to check: o 26189 Enter a string: school Enter a letter to check: o 255 g9 g2 Enter a string: school Enter a letter to check: o 261932 g9 g7 g56____490 g24 _______46____460____16199 g58 _______49____16202 g6 g006 g7 Enter a string: school Enter a letter to check: o 257 Enter a string: school Enter a letter to check: o 257
g010 Python3g011 g72
g013 g014
g015 g79 Enter a string: school Enter a letter to check: o 262092
g73 g019 g7 _______47____4022 g7 g78 g79 g80 g90
_______47____4029 _______47____4031 g7 g033 g79 Enter a string: school Enter a letter to check: o 261711 g95 g3 g84 g85 g86 g041
_______47____4043 g7 g40 g79 Enter a string: school Enter a letter to check: o 261711 g95 g3 g84 g85 g86 g041
g7 g3 g84 g85 g86 g56 g88 g89 g9 g063____479 g065 g066 g9 g7 g56_______4033 g071 g79 g79 g95 g22 g6 g033____4071 g97 g79 g90 g6 g083______479 g84 g9 g087 g56 g033 g071 g79 g79 g90 g22 g6 g033____4071 g97 g79 g90
g7 g3 g84 g85 g86 g106 g9 g7 g56_______4033 g111 g79 g79 Enter a string: school Enter a letter to check: o 262152 g22 g6 g7 g118 g79 g79 g80 g90 g22 g124 Enter a string: school Enter a letter to check: o 251 g78 g79 g128 _______46____4087____4131 Enter a string: school Enter a letter to check: o 251 g78 g79 g128 g7 Enter a string: school Enter a letter to check: o 26179 g78
g28 g7 g30 g79 g79 g144 g34 g7 g36 g79 Enter a string: school Enter a letter to check: o 26189 g7 g40 g79 Enter a string: school Enter a letter to check: o 261849 g36 g58 g7 g7 g47 g79 g79 g80 g90 g22 g9 g54____456 Enter a string: school Enter a letter to check: o 26199 g24 _______47____16202____434 _______49____454____456 g36 g65 g9 g178 g179 C#g180 g71 Enter a string: school Enter a letter to check: o 2621 g72 g41 g76 Enter a string: school Enter a letter to check: o 262069 g6 g7 g41 g79 g2 Enter a string: school Enter a letter to check: o 261849 g79 g80 g7 g6 g9 Enter a string: school Enter a letter to check: o 261854 g9 g2 Enter a string: school Enter a letter to check: o 261857 g202 g9 Enter a string: school Enter a letter to check: o 261859 g9____161861 g9 g2 g209 g9 g2 g212 Enter a string: school Enter a letter to check: o 262097 g2 Enter a string: school Enter a letter to check: o 262099 g202 g9____161866 g9 g2 g221 Enter a string: school Enter a letter to check: o 262097 g2 Enter a string: school Enter a letter to check: o 262099 g202 ________ 49 ________ 43 ________ 491 g9 g6 g6 Enter a string: school Enter a letter to check: o 261876 g2 Enter a string: school Enter a letter to check: o 261878 g6 g7 g237 g6 g6 Enter a string: school Enter a letter to check: o 251____161883 Enter a string: school Enter a letter to check: o 251 Enter a string: school Enter a letter to check: o 261885 _______46____357 g6 Enter a string: school Enter a letter to check: o 26202 g7 Enter a string: school Enter a letter to check: o 261890 Enter a string: school Enter a letter to check: o 251____161883 g9 Enter a string: school Enter a letter to check: o 257 g202 g9 g3 g257 g9 g6 g6 g7 g262 g6 g6 Enter a string: school Enter a letter to check: o 251 g7 Enter a string: school Enter a letter to check: o 261903 Enter a string: school Enter a letter to check: o 261904 g11 Enter a string: school Enter a letter to check: o 261906 Enter a string: school Enter a letter to check: o 251 Enter a string: school Enter a letter to check: o 26202 g7 Enter a string: school Enter a letter to check: o 261910 g11 Enter a string: school Enter a letter to check: o 261906 _______46____357 g9 Enter a string: school Enter a letter to check: o 257 g202 g9 Enter a string: school Enter a letter to check: o 26179 Enter a string: school Enter a letter to check: o 26180 g7 Enter a string: school Enter a letter to check: o 257 g202 _______47____16182 g7 g41 g79 g42 g294 g7 g6 g9 g79 Enter a string: school Enter a letter to check: o 2539____16189 Enter a string: school Enter a letter to check: o 255 g9 g2 Enter a string: school Enter a letter to check: o 261932 g9 g7 Enter a string: school Enter a letter to check: o 26196 _______46____4309____16199 g58 _______49____16202 _______46____4315 g7 Enter a string: school Enter a letter to check: o 257 Enter a string: school Enter a letter to check: o 257 g202 g320 JavascriptEnter a string: school Enter a letter to check: o 261775 _______47____4323 g7 g7____3564 g327 g7 g6 g9 Enter a string: school Enter a letter to check: o 261854 _______49____4333 g334 g9 Enter a string: school Enter a letter to check: o 261859 g9____161861 _______49____4340 g9____4342 Enter a string: school Enter a letter to check: o 262097 g344 _______49____4346 g334 g9____161866 g9 g351 Enter a string: school Enter a letter to check: o 262097 g344 _______49____4355 g334 g9 g3 Enter a string: school Enter a letter to check: o 261788 g9 g6 _______46____4363 g6 g7 g237 g6 g6 Enter a string: school Enter a letter to check: o 251____161883 Enter a string: school Enter a letter to check: o 251 Enter a string: school Enter a letter to check: o 261885 _______46____357 g6 Enter a string: school Enter a letter to check: o 26202 g7 Enter a string: school Enter a letter to check: o 261890 Enter a string: school Enter a letter to check: o 251____161883 g9 Enter a string: school Enter a letter to check: o 257 g334 g9 g3 g257 g9 g6 g6 g7 g262 g6 g6 Enter a string: school Enter a letter to check: o 251 g7 Enter a string: school Enter a letter to check: o 261903 Enter a string: school Enter a letter to check: o 261904 g11 Enter a string: school Enter a letter to check: o 261906 Enter a string: school Enter a letter to check: o 251 Enter a string: school Enter a letter to check: o 26202 g7 Enter a string: school Enter a letter to check: o 261910 g11 Enter a string: school Enter a letter to check: o 261906 _______46____357 g9 Enter a string: school Enter a letter to check: o 257 g334 g9 Enter a string: school Enter a letter to check: o 26179 Enter a string: school Enter a letter to check: o 26180 g7 Enter a string: school Enter a letter to check: o 257 g7 g7____161823 Enter a string: school Enter a letter to check: o 26189 Enter a string: school Enter a letter to check: o 255 _______47____4422 g7 g7 Enter a string: school Enter a letter to check: o 26196 g426 Enter a string: school Enter a letter to check: o 261830 Enter a string: school Enter a letter to check: o 26199 g58 _______47____16202 g426 Enter a string: school Enter a letter to check: o 261835
g434 Enter a string: school Enter a letter to check: o 261838 Đầu ra g Độ phức tạp về thời gian. O(N) Phương pháp #3. Sử dụng các hàm Python tích hợpCách tiếp cận
Dưới đây là việc thực hiện Python3g436 ________ 4437 ________ 4438 ________ 472 ________ 4440
g441 g442 g73 g444 g334 _______47____4447 _______47____4449 g7____4451____479 g453 g7 _______47____4456 g7 g3 g84 g85 g461 g9 g7____4464 g90 g22 _______46____454____4469 _______46____354
g28 ________ 479 ________ 479 ________ 16189
g476 g477
g478 Đầu ra g Độ phức tạp về thời gian. O(n) Phương pháp #4. Giải chỉ bằng cách duyệt một chuỗi đã cho
C++g479 g480 g481 Enter a string: school Enter a letter to check: o 2621 g0 g1
g485 g4 g487 g7 g6 _______49____4491____44____499 g2 g495 g9 g4 g498 g499 Enter a string: school Enter a letter to check: o 255 ________ 49 ________ 42 ________ 4503 g9 _______49____4506 g9 g3____456 g2 g511 g9 g6 ________ 46 ________ 44 ________ 4516 g6 _______46____47____4520 _______46____16202 g6 g6 Enter a string: school Enter a letter to check: o 251____47____4527 Enter a string: school Enter a letter to check: o 251 g6 _______411____4531 _______411____4533 Enter a string: school Enter a letter to check: o 251 Enter a string: school Enter a letter to check: o 257 _______46____357 g6 g9 Enter a string: school Enter a letter to check: o 257 g9 g9 ________ 49 ________ 16179 ________ 4545 g7 Enter a string: school Enter a letter to check: o 257
g548 g2 g550
_______47____4552 _______47____4554____4555 Enter a string: school Enter a letter to check: o 255 _______47____4558 g7 g7 Enter a string: school Enter a letter to check: o 26179 Enter a string: school Enter a letter to check: o 26207 Enter a string: school Enter a letter to check: o 257
Enter a string: school Enter a letter to check: o 26209 g565 Javag566 g567 g72 g75
g41 g76 g77 g334 g41 g79 g2 g577 g578 Enter a string: school Enter a letter to check: o 255
_______4334____4485 ________ 4334 g41 ________ 479 ________ 44 ________ 4586 g334 g6 _______47____4590 g426 g79 Enter a string: school Enter a letter to check: o 262097 g594 g7 g4 g597____4499 Enter a string: school Enter a letter to check: o 255 g7 g2 g602
_______47____4506 g7 g3 g56 g2 g609 g95 g611 ________ 4426 ________ 44 ________ 4614
g426 g7 g617 _______49____4619 _______4426____357 g426 Enter a string: school Enter a letter to check: o 26202 g6 g9 g7 g627 g628 g629 g628 g631 g9 Enter a string: school Enter a letter to check: o 257 _______4426____357 g7 Enter a string: school Enter a letter to check: o 257
g7 Enter a string: school Enter a letter to check: o 26179 g545 g334 Enter a string: school Enter a letter to check: o 257
g334 g548 g334 g41 g79 g42 Enter a string: school Enter a letter to check: o 262184 g334 g6
_______47____4552 _______47____4655____4555 Enter a string: school Enter a letter to check: o 255 _______47____4659 _______47____4661____4662 g58 g334 Enter a string: school Enter a letter to check: o 257 Enter a string: school Enter a letter to check: o 257
g667 Python3g668 g669 ________ 4670 ________ 479 ________ 4578
g673 g73 g675 g7 g677 g79 g679 g680 g7 g682______479 g499 g7 g686______479 g670 g7 _______47____4691 g7 g84 g79 g95 g7 g697 g698 g88 g89 g9 g78 g79 g704 g9 g7 g56____4708 g118 g85 g677 g712 g6 g677____4715 g79 g84 g9 Enter a string: school Enter a letter to check: o 26202____434 g6 g7 g56____4677 g725 Enter a string: school Enter a letter to check: o 251 g686 g79 g677 g730 Enter a string: school Enter a letter to check: o 251 g682 g79 g78 g9 g84 g97 g79 g90 g7 Enter a string: school Enter a letter to check: o 26179 g682
g7 g30 g79 g79 g33 g34 g334 _______47____4751 g7____4753____479 g555 _______47____454____4758____479 g760 _______47____454____456 g662 g765 g79 g760
g768 C#g769 Enter a string: school Enter a letter to check: o 2621 g72 Enter a string: school Enter a letter to check: o 2621 g773
________ 441 ________ 479 ________ 476 ________ 477 g334 g79 g2 g781
_______4334____4485 g334 g41 g79 g4 g788 g79 g80 g334 g6 _______47____4794____44____499 g2 g798 g426 g79 Enter a string: school Enter a letter to check: o 262097 g794 g4 g99 g2 g806 g7 g4 g597____4499 Enter a string: school Enter a letter to check: o 255 g7 g2 g602
_______47____4506 g7 g3 g56______42 g821 g426 g4 g824
g426 g7 g827 _______49____4829 _______4426____357 g426 Enter a string: school Enter a letter to check: o 26202 g6 g9 g7 g837 g628 g839 g628 g631 g9 Enter a string: school Enter a letter to check: o 257 _______4426____357 g7 Enter a string: school Enter a letter to check: o 257
g7 Enter a string: school Enter a letter to check: o 26179 g545 g334 Enter a string: school Enter a letter to check: o 257
g334 g548 ________ 4334 g41 ________ 479 ________ 442 ________ 4294 g334 g6
_______47____4552 g7 g79 g866 g555 Enter a string: school Enter a letter to check: o 255 _______47____4870 _______47____4309____4662 g58 g334 Enter a string: school Enter a letter to check: o 257 Enter a string: school Enter a letter to check: o 257
g667 JavascriptEnter a string: school Enter a letter to check: o 261775 g880 g881
g485 Enter a string: school Enter a letter to check: o 2564 g884 g6 g7____4887 Enter a string: school Enter a letter to check: o 262097 g889 g7____4891____4499 Enter a string: school Enter a letter to check: o 255 _______47____4895 g9 _______47____4506 _______47____43____4901 g7 g6 g9 g905 g6 g9 g7____4909 _______49____16202 g9 g6 _______46____47____4916 g6 g6 _______351____4629 Enter a string: school Enter a letter to check: o 251____4631 _______46____357 _______49____4926 g7 Enter a string: school Enter a letter to check: o 257 g7 Enter a string: school Enter a letter to check: o 26179 g545 Enter a string: school Enter a letter to check: o 257
Enter a string: school Enter a letter to check: o 26182
g552 ________ 4935 ________ 4555 ________ 355 g938 g7 g940 Enter a string: school Enter a letter to check: o 261838 Đầu ra Enter a string: school Enter a letter to check: o 25 Độ phức tạp về thời gian. O(N) Giải pháp tối ưu hơn Ký tự lặp lại có lần xuất hiện đầu tiên ở ngoài cùng bên trái Bài viết này được đóng góp bởi Suprotik Dey. Nếu bạn thích GeeksforGeeks và muốn đóng góp, bạn cũng có thể viết một bài báo bằng cách sử dụng write. chuyên viên máy tính. org hoặc gửi bài viết của bạn tới review-team@geeksforgeeks. tổ chức. Xem bài viết của bạn xuất hiện trên trang chính của GeeksforGeeks và trợ giúp các Geeks khác Làm cách nào để kiểm tra các ký tự lặp lại trong một chuỗi trong JavaScript?Làm cách nào để tìm các ký tự trùng lặp trong một chuỗi JavaScript đã cho? . const getRepeatedChars = (str) => { cho (const char của str) { ký tự [char] = (ký tự [char]. 0) + 1; trả lại đối tượng. mục nhập (ký tự). bộ lọc (char => char[1] > 1). bản đồ(char => char[0]); Làm cách nào để tìm các bản sao trong một chuỗi trong JavaScript?hàm hasDuplicates (mảng) { var count = []; . chiều dài; . ] var mảng = [1, 1, 2, 3, 4]; . bạn có các giá trị trùng lặp
Làm cách nào để tìm các ký tự trùng lặp trong JavaScript?Cách tiếp cận. Tạo một HashMap và ký tự của Chuỗi sẽ được chèn làm khóa và được tính là giá trị. Nếu Hashamap đã chứa char, hãy tăng số lượng của nó lên 1, nếu không thì hãy đặt char trong HashMap. Nếu giá trị của Char lớn hơn 1, điều đó có nghĩa là nó là ký tự trùng lặp trong Chuỗi đó
Làm cách nào để đếm số lần xuất hiện của một ký tự trong chuỗi trong JavaScript?Ví dụ 2. Kiểm tra sự xuất hiện của một ký tự bằng Regex
. const re = new RegExp(letter, 'g'); . Phương thức match() trả về một mảng chứa tất cả các kết quả khớp. |