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Refactor the articles related to searching algorithm. Add the chapter of binary search. Add the section of searching algorithm revisited. (#464)

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Yudong Jin
2023-04-17 18:22:18 +08:00
committed by GitHub
parent 28fdd26f2f
commit 881d573790
57 changed files with 265 additions and 505 deletions
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45
codes/javascript/chapter_computational_complexity/leetcode_two_sum.js
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@ -1,45 +0,0 @@
/**
* File: leetcode_two_sum.js
* Created Time: 2022-12-15
* Author: gyt95 (gytkwan@gmail.com)
*/
/* 方法一：暴力枚举 */
function twoSumBruteForce(nums, target) {
const n = nums.length;
// 两层循环，时间复杂度 O(n^2)
for (let i = 0; i < n; i++) {
for (let j = i + 1; j < n; j++) {
if (nums[i] + nums[j] === target) {
return [i, j];
}
}
}
return [];
}
/* 方法二：辅助哈希表 */
function twoSumHashTable(nums, target) {
// 辅助哈希表，空间复杂度 O(n)
let m = {};
// 单层循环，时间复杂度 O(n)
for (let i = 0; i < nums.length; i++) {
if (m[nums[i]] !== undefined) {
return [m[nums[i]], i];
} else {
m[target - nums[i]] = i;
}
}
return [];
}
/* Driver Code */
// 方法一
const nums = [2, 7, 11, 15], target = 9;
let res = twoSumBruteForce(nums, target);
console.log("方法一 res = ", res);
// 方法二
res = twoSumHashTable(nums, target);
console.log("方法二 res = ", res);