leetcode刷题 js版

刷题地址在这leetcode

当然网址上也会有java版的解答, 涉及优化的细节

1. Two Sum

/**
 * @param {number[]} nums
 * @param {number} target
 * @return {number[]}
 */
// Approach 1: Brute Force
var twoSum = function(nums, target) {
  for( let i = 0; i < nums.length; i++) {
    for(let j = i+1; j < nums.length; j++) {
      if (nums[j] === target - nums[i]) {
        return [i,j]
      }
    }
  }
};
// Approach 2: Two-pass Hash Table
var twoSum = function(nums, target) {
  const map = new Map()
  for(let i = 0; i < nums.length; i++) {
    map.set(nums[i], i);
  }
  for(let i = 0; i < nums.length; i++) {
    let complement = target - nums[i];
    if (map.has(complement) && map.get(complement) != i) {
      return [map.get(complement), i]
    }
  }
};
// Approach 3: One-pass Hash Table
var twoSum = function(nums, target) {
  const map = new Map()
  for(let i = 0; i < nums.length; i++) {
    let complement = target - nums[i];
    if (map.has(complement)) {
      return [map.get(complement), i]
    }
    map.set(nums[i], i)
  }
};

2. Add Two Numbers

5. Longest Palindromic Substring

参考

LeetCode solutions with JavaScript
chihungyu1116/leetcode-javascript
Demonstrate all the questions on LeetCode in the form of animation.