1#include <stdio.h>
2#include <stdlib.h>
3
4int compare(const void *a, const void *b) {
5    return (*(int*)a - *(int*)b);
6}
7
8int specialArray(int* nums, int numsSize) {
9    qsort(nums, numsSize, sizeof(int), compare);
10    for (int x = 0; x <= numsSize; x++) {
11        int count = 0;
12        for (int i = 0; i < numsSize; i++) {
13            if (nums[i] >= x) {
14                count++;
15            }
16        }
17        if (count == x) {
18            return x;
19        }
20    }
21    return -1;
22}
23
24int main() {
25    int nums[] = {0, 4, 3, 0, 4};
26    int numsSize = sizeof(nums) / sizeof(nums[0]);
27    int result = specialArray(nums, numsSize);
28    printf("%d\n", result);
29    return 0;
30}

1