2003 수들의 합(2)

#include <stdio.h>
 
int arr[10001] = { 0 };
 
int main() {
    int n, m;
    scanf("%d %d", &n, &m);
    getchar();
 
    for (int i = 0; i < n; i++) {
        scanf("%d", &arr[i]);    
    }
 
    int low = 0, high = 0, sum = arr[0];
    int tmp = 0;
    while (low <= high&&high < n) {
        if (sum < m) {            
            sum += arr[++high];
        }
        else if (sum == m) {
            tmp++;            
            sum += arr[++high];            
        }
        else {
            sum -= arr[low++];
            
            if (low > high&&low < n) {
                high = low;
                sum = arr[low];
            }            
        }
    }
    printf("%d\n", tmp);
}