LeetCode*1. Two Sum

LeetCode题目链接

题目：

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, and you may not use the same element twice.

Example:

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

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

答案（常规解法）：

class Solution {
public:
    vector<int> twoSum(vector<int>& nums, int target) {
        vector<int> resArr;
        for (int i = 0; i < nums.size(); i++) {
                vector<int>::iterator res = find(nums.begin() + i + 1, nums.end(), target - nums[i] );
                
                if (res != nums.end()) {          /* find the number */
                    resArr.push_back(i);
                    for (int j = i + 1; j < nums.size(); j++) {
                        if (nums.at(j) == (*res)) {
                            resArr.push_back(j);
                        }
                    }
                    
                    return resArr;
                }
        }
        return resArr;
    }
};