Roman To Integer about daily-algorithms HOT 2 OPEN

function resolve(roman) {
  var map = {
    M: 1000, 
    D: 500, 
    C: 100,
    L: 50, 
    X: 10,
    V: 5, 
    I: 1
  };
  var index = 0, integer = 0;
  while(roman[index++]) {
    integer += map[roman[index - 1]] * (
      map[roman[index - 1]] < (map[roman[index]] || 0) ? -1 : 1
    );
  }
  return integer;
}

console.assert(resolve('MCDXXXVII') === 1437, 1437);

var romanToInt = function(s) {
    const romanMap = {
      I: 1,
      V: 5,
      X: 10,
      L: 50,
      C: 100,
      D: 500,
      M: 1000
    };
    const tempArr = s.split("");
    let result = 0;
    tempArr.forEach((item, index) => {
      const next = romanMap[tempArr[index+1]];
      const current = romanMap[tempArr[index]];
      const pre = index>=1 ? romanMap[tempArr[index-1]] : false;
      if (next>current && pre != current) {
        result -= current;
      } else {
        result += current;
      }
    });
    return result;
};