这是LeetCode的第一道题，请问如图位置应该输入什么参数？

#include<stdio.h>
#include<malloc.h>
int* twoSum(int* nums, int numsSize, int target, int* returnSize);
int main()
{
    int a[4] = { 2, 7, 11, 15 };
    twoSum(a, 4, 9, 0);
    return 0;
}
int* twoSum(int* nums, int numsSize, int target, int* returnSize) {
    int* a = (int*)malloc(sizeof(int) * 2);
    int i, j;
    for (i = 0; i < numsSize - 1; i++) {
        for (j = i + 1; j < numsSize; j++) {
            if (nums[i] + nums[j] == target) {
                a[0] = i;
                a[1] = j;
                *returnSize = 2;
                return a;
            }
        }
    }
    *returnSize = 0;
    return a;
}

int a[4] = {2,7,11,15};
int returnsize; //加上
twoSum(a, 4, 9, &returnsize);
return 0;