1. Two Sum

• Total Accepted: 259837
• Total Submissions: 1043139
• 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.

 

思路：直接看代码。

 

代码：

1 class Solution { 2 public: 3     vector
     
       twoSum(vector
      
       & nums, int target) { 4         unordered_map
       
         imap; 5         vector
        
          res; 6         int i,n=nums.size(); 7         for(i=0;i