Hướng dẫn roman numeral converter javascript freecodecamp - công cụ chuyển đổi chữ số la mã javascript freecodecamp

Sự mô tả

Xét nghiệm

tests:
  - text: convertToRoman[2] should return "II".
    testString: assert.deepEqual[convertToRoman[2], "II"];
  - text: convertToRoman[3] should return "III".
    testString: assert.deepEqual[convertToRoman[3], "III"];
  - text: convertToRoman[4] should return "IV".
    testString: assert.deepEqual[convertToRoman[4], "IV"];
  - text: convertToRoman[5] should return "V".
    testString: assert.deepEqual[convertToRoman[5], "V"];
  - text: convertToRoman[9] should return "IX".
    testString: assert.deepEqual[convertToRoman[9], "IX"];
  - text: convertToRoman[12] should return "XII".
    testString: assert.deepEqual[convertToRoman[12], "XII"];
  - text: convertToRoman[16] should return "XVI".
    testString: assert.deepEqual[convertToRoman[16], "XVI"];
  - text: convertToRoman[29] should return "XXIX".
    testString: assert.deepEqual[convertToRoman[29], "XXIX"];
  - text: convertToRoman[44] should return "XLIV".
    testString: assert.deepEqual[convertToRoman[44], "XLIV"];
  - text: convertToRoman[45] should return "XLV"
    testString: assert.deepEqual[convertToRoman[45], "XLV"];
  - text: convertToRoman[68] should return "LXVIII"
    testString: assert.deepEqual[convertToRoman[68], "LXVIII"];
  - text: convertToRoman[83] should return "LXXXIII"
    testString: assert.deepEqual[convertToRoman[83], "LXXXIII"];
  - text: convertToRoman[97] should return "XCVII"
    testString: assert.deepEqual[convertToRoman[97], "XCVII"];
  - text: convertToRoman[99] should return "XCIX"
    testString: assert.deepEqual[convertToRoman[99], "XCIX"];
  - text: convertToRoman[400] should return "CD"
    testString: assert.deepEqual[convertToRoman[400], "CD"];
  - text: convertToRoman[500] should return "D"
    testString: assert.deepEqual[convertToRoman[500], "D"];
  - text: convertToRoman[501] should return "DI"
    testString: assert.deepEqual[convertToRoman[501], "DI"];
  - text: convertToRoman[649] should return "DCXLIX"
    testString: assert.deepEqual[convertToRoman[649], "DCXLIX"];
  - text: convertToRoman[798] should return "DCCXCVIII"
    testString: assert.deepEqual[convertToRoman[798], "DCCXCVIII"];
  - text: convertToRoman[891] should return "DCCCXCI"
    testString: assert.deepEqual[convertToRoman[891], "DCCCXCI"];
  - text: convertToRoman[1000] should return "M"
    testString: assert.deepEqual[convertToRoman[1000], "M"];
  - text: convertToRoman[1004] should return "MIV"
    testString: assert.deepEqual[convertToRoman[1004], "MIV"];
  - text: convertToRoman[1006] should return "MVI"
    testString: assert.deepEqual[convertToRoman[1006], "MVI"];
  - text: convertToRoman[1023] should return "MXXIII"
    testString: assert.deepEqual[convertToRoman[1023], "MXXIII"];
  - text: convertToRoman[2014] should return "MMXIV"
    testString: assert.deepEqual[convertToRoman[2014], "MMXIV"];
  - text: convertToRoman[3999] should return "MMMCMXCIX"
    testString: assert.deepEqual[convertToRoman[3999], "MMMCMXCIX"];

Dung dịch

function convertToRoman[num] {
  var ref = [['M', 1000], ['CM', 900], ['D', 500], ['CD', 400], ['C', 100], ['XC', 90], ['L', 50], ['XL', 40], ['X', 10], ['IX', 9], ['V', 5], ['IV', 4], ['I', 1]];
  var res = [];
  ref.forEach[function[p] {
    while [num >= p[1]] {
      res.push[p[0]];
      num -= p[1];
    }
  }];
  return res.join[''];
}

function convertToRoman[num] {
//Break the number into Thousands, Hundreds, Tens and Ones, and write down each in turn.
//get the digits
const numStr=num.toString[];
const len=numStr.length;
let Thousands=0,Hundreds= 0,Tens= 0;
if[len>=2]{Tens=parseInt[numStr[len-1-1]];}
if[len>=3]{Hundreds=parseInt[numStr[len-1-2]];}
if[len==4]{Thousands=parseInt[numStr[0]];}
const Ones=num%10;
const lookup=[
    ["","I","II","III","IV","V","VI","VII","VIII","IX"],
    ["","X","XX","XXX","XL","L","LX","LXX","LXXX","XC"],
    ["","C","CC","CCC","CD","D","DC","DCC","DCCC","CM"],
    ["","M","MM","MMM"]];
return lookup[3][Thousands]+lookup[2][Hundreds]+
lookup[1][Tens]+lookup[0][Ones];
}

convertToRoman[36];

var convertToRoman = function[num] {
  var decimalValue = [1000, 900, 500, 400, 100, 90, 50, 40, 10, 9, 5, 4, 1];
  var romanNumeral = ['M', 'CM', 'D', 'CD', 'C', 'XC', 'L', 'XL', 'X', 'IX', 'V', 'IV', 'I'];

  var romanized = "";

  for [var index = 0; index