Given a positive number, check if it is a power of four or not.
Practice this problem
Approach 1
A simple solution is to calculate log4n for a given number n. If it returns an integral value, then we can say that the number is a power of four.
This approach is demonstrated below in C++, Java, and Python:
C++
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 | #include #include usingnamespacestd; // Returns true if `n` is a power of four boolcheckPowerOf4[unsignedn] { // find `log4[n]` doublei=log[n]/ log[4]; // return true if `log4[n]` is an integer return i==trunc[i]; } int main[] { unsignedn= 256; if[checkPowerOf4[n]]{ cout Chủ Đề |