leetcode 001 Two Sun

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].

//时间O(N^2) 你的平方    空间 O(1)
int* twoSum_1(int* nums, int numsSize, int target) {
    int i=0;
    int j=0;
    int *rtn=NULL;
    for(i=0;i<numsSize-1;i++)
    {
        for(j=i+1;j<numsSize;j++)
        {
            if(target-nums[j]==nums[i])
            {
               rtn=malloc(2*sizeof(int));
               rtn[0]=i;
               rtn[1]=j;
               return rtn;

            }
        }
    }
    return rtn;
}