LeetCode:Two Sum

最新推荐文章于 2019-01-03 13:40:30 发布

原创最新推荐文章于 2019-01-03 13:40:30 发布 · 783 阅读

0 ·

CC 4.0 BY-SA版权

文章标签：

#LeetCode #Two Sum

LeetCode OJ 同时被 2 个专栏收录

216 篇文章

订阅专栏

LeetCode解题记录

216 篇文章

订阅专栏

本文介绍了一个简单的算法来解决数组中寻找两个数相加等于目标数的问题，适用于初学者理解基本的数组操作和哈希表应用。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

Two Sum

Total Accepted: 199288 Total Submissions: 913621 Difficulty: Easy

Given an array of integers, return indices of the two numbers such that they add up to a specific target.

You may assume that each input would have exactly one solution.

Example:

Given nums = [2, 7, 11, 15], target = 9,

Because nums[0] + nums[1] = 2 + 7 = 9,
return [0, 1].

UPDATE (2016/2/13):
The return format had been changed to zero-based indices. Please read the above updated description carefully.

Hide Tags

Array Hash Table

Hide Similar Problems

(M) 3Sum (M) 4Sum (M) Two Sum II - Input array is sorted (E) Two Sum III - Data structure design

code:

class Solution {
public:
    vector<int> twoSum(vector<int>& nums, int target) {
        map<int,int> m;
        vector<int> ret;
        for(int i=0;i<nums.size();i++){
            m[nums[i]]=i;
        }
        for(int i=0;i<nums.size();i++){
            int tmp = target-nums[i];
            if(m.find(tmp)!=m.end() && m[tmp]>i){
                ret.push_back(i);
                ret.push_back(m[tmp]);
                break;
            }
        }
        return ret;
    }
};