UvaLive LA2678 Subsequence

#include <cstdio>
#include <cstring>
#include <algorithm>

using namespace std;

const int maxn = 100001;
int A[maxn],B[maxn];

int main() {
int n,S;
while(~scanf("%d%d",&n,&S)) {
int ans = 0;
for(int i = 1;i <= n;i++) {
scanf("%d",&A[i]);
B[i] = B[i - 1] + A[i];
int str = 1,end = i;
while(str < end) {
int mid = str + (end - str + 1) / 2;
if(B[i] - B[mid - 1] < S) {
end = mid - 1;
} else {
str = mid;
}
}
if(B[i] - B[str - 1] >= S) {
if(ans == 0) ans = i - str + 1;
else ans = min(ans,i - str + 1);
}
}
printf("%d\n",ans);
}
return 0;
}