1300.转变数组后最接近目标值的数组和

链接：1300.转变数组后最接近目标值的数组和
难度：Medium
标签：数组、二分查找、排序
简介：排序后进行判断，四舍五入

题解 1 - typescript

• 编辑时间：2020-06-17
• 执行用时：96ms
• 内存消耗：36MB
• 编程语言：typescript
• 解法介绍：description。

function findBestValue(arr: number[], target: number): number {
  const len = arr.length;
  if (len === 1) return target > arr[0] ? target : arr[0];
  arr.sort((a, b) => a - b);
  let sum = 0;
  let min = Infinity;
  let cha = Infinity;
  for (let i = 0; i < len; i++) {
    const num = arr[i];
    const sLen = len - i - 1;
    sum += num;
    const need = Math.round((target - sum) / sLen);
    if (need < num || (i !== len - 1 && need > arr[i + 1])) continue;
    const newCha = Math.abs(need * sLen + sum - target);
    compCha(newCha, need);
    const newCha2 = Math.abs((need - 1) * sLen + sum - target);
    compCha(newCha2, need - 1);
  }
  if (min === Infinity) {
    const num = Math.round(target / len);
    if (num < arr[0]) {
      const newCha = Math.abs(num * len - target);
      compCha(newCha, num);
    }
  }
  compCha(Math.abs(target - sum), arr[len - 1]);
  return min;
  function compCha(newCha: number, need: number): void {
    if (newCha < cha || (newCha === cha && need < min)) {
      cha = newCha;
      min = need;
    }
  }
}