算法题：13. 罗马数字转整数

题

解

function romanToInt(s: string): number {
    const map = {
        I: 1,
        V: 5,
        X: 10,
        L: 50,
        C: 100,
        D: 500,
        M: 1000,

        IV: 4,
        IX: 9,
        XL: 40,
        XC: 90,
        CD: 400,
        CM: 900,
    };
    let i = 0;
    let sum = 0;
    let next = '';
    let v = '';
    while (i < s.length) {
        next = s[i + 1];
        v = s[i];
        if (next && map[v + next]) {
            sum += map[v + next];
            i += 2;
        } else {
            sum += map[v];
            i++;
        }
    }
    return sum;
}