Task for JavaScript developer vacancy by Ihor Tsarenko

RomanToInteger.js

https://leetcode.com/problems/roman-to-integer/

Here is my solution:

const romanToInt = str => {
    const VALUES = {
      M: 1000,
      D: 500,
      C: 100,
      L: 50,
      X: 10,
      V: 5,
      I: 1
    };

    let prev = 0;
    let sum = 0;
    for (let i = 0; i < str.length; i++) {
      let curr = VALUES[str[i]];
      sum += prev < curr ? curr - 2 * prev : curr;
      prev = curr;
    }
    return sum;
  }