Hackerrank: Counting Valleys Solution

1function countingValleys(steps, path) {
2  let res = 0
3  let curr = 0
4  const splitedPath = path.split("")
5  const mapped = [0, ...splitedPath.map(p => (curr += { U: 1, D: -1 }[p]))]
6  let i = 0
7  while (i < steps) {
8    if (mapped[i] === 0) {
9      while (mapped[++i] !== 0 && i < steps) {}
10      if (mapped[i - 1] < 0) res++
11    }
12  }
13  return res
14}