LeetCode:Two Sum

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.

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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;
    }
};