Can Find Zero

canFindZero.js

const digits = [3, 7, 0, 2, 8, 3, 7, 6];
const digits_empty = [];

function canFindZero(values, startIndex, checkedIndexes) {
  checkedIndexes.push(startIndex);
  if (values[startIndex] === 0) {
    return true;
  }
  const leftIndex = startIndex - values[startIndex];
  const leftIndexValue = values[leftIndex];
  if (leftIndexValue && !checkedIndexes.includes(leftIndex)) {
    checkedIndexes.push(leftIndex);
    const canFindZeroLeft = canFindZero(values, leftIndexValue, checkedIndexes);
    if (canFindZeroLeft) {
      return true;
    }
  }
  const rightIndex = startIndex + values[startIndex];
  const rightIndexValue = values[rightIndex];
  if (rightIndexValue && !checkedIndexes.includes(rightIndex)) {
    checkedIndexes.push(rightIndex);
    const canFindZeroRight = canFindZero(values, rightIndexValue, checkedIndexes);
    if (canFindZeroRight) {
      return true;
    }
  }
  return false;
}

console.log(canFindZero(digits, 0, []) === true);
console.log(canFindZero(digits, 4, []) === false);
console.log(canFindZero(digits_empty, 0, []) === false);