1#include <stdio.h>
2#include <limits.h>
3#include <stdlib.h>
4
5int shortestSubarray(int* nums, int numsSize, int k) {
6    int* prefixSum = (int*) malloc((numsSize + 1) * sizeof(int));
7    prefixSum[0] = 0;
8    for (int i = 0; i < numsSize; ++i) {
9        prefixSum[i + 1] = prefixSum[i] + nums[i];
10    }
11    
12    int deque[numsSize + 1];
13    int front = 0, back = 0;
14    int result = INT_MAX;
15    
16    for (int i = 0; i <= numsSize; ++i) {
17        while (front < back && prefixSum[i] - prefixSum[deque[front]] >= k) {
18            if (result > i - deque[front])
19                result = i - deque[front];
20            front++;
21        }
22        while (front < back && prefixSum[i] <= prefixSum[deque[back - 1]])
23            back--;
24        deque[back++] = i;
25    }
26    free(prefixSum);
27    return result == INT_MAX ? -1 : result;
28}
29
30int main() {
31    int nums[] = {2, -1, 2};
32    int k = 3;
33    int result = shortestSubarray(nums, 3, k);
34    printf("%d\n", result); // Output: 3
35    return 0;
36}