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更新了三数之和javascript版本

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eat to 160 pounds
2022-04-24 21:05:31 +08:00
parent 361e99262a
commit d5f21d5341
1 changed files with 26 additions and 44 deletions
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70
problems/0015.三数之和.md
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@ -313,54 +313,36 @@ func threeSum(nums []int)[][]int{
javaScript: javaScript:
```js ```js
/**
* @param {number[]} nums
* @return {number[][]}
*/
// 循环内不考虑去重
var threeSum = function(nums) { var threeSum = function(nums) {
const len = nums.length; const res = [], len = nums.length
if(len < 3) return []; // 将数组排序
nums.sort((a, b) => a - b); nums.sort((a, b) => a - b)
const resSet = new Set(); for (let i = 0; i < len; i++) {
for(let i = 0; i < len - 2; i++) { let l = i + 1, r = len - 1, iNum = nums[i]
if(nums[i] > 0) break; // 数组排过序，如果第一个数大于0直接返回res
let l = i + 1, r = len - 1; if (iNum > 0) return res
// 去重
if (iNum == nums[i - 1]) continue
while(l < r) { while(l < r) {
const sum = nums[i] + nums[l] + nums[r]; let lNum = nums[l], rNum = nums[r], threeSum = iNum + lNum + rNum
if(sum < 0) { l++; continue }; // 三数之和小于0，则左指针向右移动
if(sum > 0) { r--; continue }; if (threeSum < 0) l++
resSet.add(`${nums[i]},${nums[l]},${nums[r]}`); else if (threeSum > 0) r--
l++; else {
r--; res.push([iNum, lNum, rNum])
// 去重
while(l < r && nums[l] == nums[l + 1]){
l++
}
while(l < r && nums[r] == nums[r - 1]) {
r--
}
l++
r--
}
} }
} }
return Array.from(resSet).map(i => i.split(",")); return res
};
// 去重优化
var threeSum = function(nums) {
const len = nums.length;
if(len < 3) return [];
nums.sort((a, b) => a - b);
const res = [];
for(let i = 0; i < len - 2; i++) {
if(nums[i] > 0) break;
// a去重
if(i > 0 && nums[i] === nums[i - 1]) continue;
let l = i + 1, r = len - 1;
while(l < r) {
const sum = nums[i] + nums[l] + nums[r];
if(sum < 0) { l++; continue };
if(sum > 0) { r--; continue };
res.push([nums[i], nums[l], nums[r]])
// b c 去重
while(l < r && nums[l] === nums[++l]);
while(l < r && nums[r] === nums[--r]);
}
}
return res;
}; };
``` ```
TypeScript: TypeScript: