2582-pass-the-pillow.js

/**
 * 2582. Pass the Pillow
 * https://leetcode.com/problems/pass-the-pillow/
 * Difficulty: Easy
 *
 * There are n people standing in a line labeled from 1 to n. The first person in the line is
 * holding a pillow initially. Every second, the person holding the pillow passes it to the
 * next person standing in the line. Once the pillow reaches the end of the line, the direction
 * changes, and people continue passing the pillow in the opposite direction.
 * - For example, once the pillow reaches the nth person they pass it to the n - 1th person,
 *   then to the n - 2th person and so on.
 *
 * Given the two positive integers n and time, return the index of the person holding the pillow
 * after time seconds.
 */

/**
 * @param {number} n
 * @param {number} time
 * @return {number}
 */
var passThePillow = function(n, time) {
  const position = time % (2 * (n - 1));
  return position < n ? position + 1 : 2 * n - position - 1;
};