LeetCode Two Sum

链接: https://oj.leetcode.com/problems/two-sum/

在一个数组中找出两个值,使得他们的和等于 target; 返回相应的下标+1

依次查找是存在值等于 target-numbers[i]

class Solution
{
	public:
		vector<int> twoSum(vector<int> &numbers,int target)
		{
			map<int,int> nummap;
			vector<int> ans;
			map<int,int>::iterator iter;	
			for(int i=0;i<numbers.size();i++)
			{
				iter=nummap.find(target-numbers[i]);
				if(iter!=nummap.end())
				{
					ans.push_back(iter->second);
					ans.push_back(i+1);
					break;
				}
				else
				{
					nummap[numbers[i]]=i+1;
				}
			}
			return ans;

		}
};