05 一次编辑

一次编辑

题目描述

字符串有三种编辑操作:插入一个字符、删除一个字符或者替换一个字符。 给定两个字符串，编写一个函数判定它们是否只需要一次(或者零次)编辑。

示例 1:

输入: first = “pale” second = “ple” 输出: True

示例 2:

输入: first = “pales” second = “pal” 输出: False

代码

/**
 * @param {string} first
 * @param {string} second
 * @return {boolean}
 */
var oneEditAway = function (first, second) {
  if (first === second) return true;

  const length1 = first.length;
  const length2 = second.length;
  if (Math.abs(length1 - length2) > 1) return false;

  if (length1 === length2) {
    // 长度一致时，尝试替换字符
    let wrongSize = 0;
    for (let i = 0; i < length1; i++) {
      if (first[i] !== second[i]) wrongSize++;
    }
    return wrongSize === 1;
  } else {
    let wrongIndex = 0;
    // 长度不一致时，尝试添加或删除一个字符
    for (let i = 0; i < Math.max(length1, length2); i++) {
      if (first[i] !== second[i]) {
        wrongIndex = i;
        break;
      }
    }
    return (
      first.slice(0, wrongIndex) + first.slice(wrongIndex + 1) === second ||
      first === second.slice(0, wrongIndex) + second.slice(wrongIndex + 1)
    );
  }
};