1551.使数组中所有元素相等的最小操作数.js

/*
 * @lc app=leetcode.cn id=1551 lang=javascript
 *
 * [1551] 使数组中所有元素相等的最小操作数
 */

// @lc code=start
/**
 * @param {number} n
 * @return {number}
 */

/**
 * 1  [1] 0 （0）
 * 2  [1,3] [2,2] 1 （1）
 * 3  [1, 3, 5] [2,3,4] [3,3,3] 2 （2）
 * 4  [1, 3, 5, 7] [2,3,5,6] [3,3,5,5] [4,3,5,4][4,4,4,4] 4 （3+1）
 * 5  [1, 3, 5, 7, 9] [2,3,5,7,8][3,3,5,7,7][4,3,5,7,6][4,4,5,6,6][5,4,5,6,5][5,5,5,5,5] 6 （4+2）
 * 6  [1,3,5,7,9,11] [2,3,5,7,9,10] [3,3,5,7,9,9] [4,3,5,7,9,8][4,4,5,7,8,8][5,4,5,7,8,7][5,5,5,7,7,7] [6,5,5,6,7,7]
 *    [6,6,5,6,6,7][6,6,6,6,6,6] 9 （5+3+1）
 * 7  [1,3,5,7,9,11,13][2,3,5,7,9,11,12][3,3,5,7,9,11,11][4,3,5,7,9,11,10][4,4,5,7,9,10,10][5,4,5,7,9,10,9][5,5,5,7,9,9,9]
 *    [6,5,5,7,8,9,9][6,6,5,7,8,8,9][6,6,6,7,8,8,8] ... 12 （6+4+2）
 */
var minOperations = function (n) {
  let res = 0;
  let i = n % 2 ? 2 : 1;
  for (; i < n; i += 2) {
    res += i;
  }
  return res;
};
// @lc code=end