Description:
Given a roman numeral, convert it to an integer.
Input is guaranteed to be within the range from 1 to 3999.
My code:
/**
* @param {string} s
* @return {number}
*/
var romanToInt = function(s) {
var sum = 0;
var romanToIntObj = {
'I': 1,
'V': 5,
'X': 10,
'L': 50,
'C': 100,
'D': 500,
'M': 1000
};
var romanArr = s.split("");
for(let i = 0; i < romanArr.length; i++) {
var cur, next;
if(i == romanArr.length - 1) {
sum += romanToIntObj[romanArr[i]];
} else {
cur = romanArr[i];
next = romanArr[i + 1];
if(romanToIntObj[cur] < romanToIntObj[next]) {
sum -= romanToIntObj[cur];
} else {
sum += romanToIntObj[cur];
}
}
}
return sum;
};
Note: 按照每一位判断应该加还是减即可。
