C ++代码的优化

Question

This is my solution to Spoj 11373. Coke madness

#include <cstdio>

int main(){
    int T; scanf("%d",&T);

    for(int j = 1; j <= T; j++){
        int n;
        scanf("%d",&n);
        long long sum = 0, small = 0;
        int t;
        for(int i = 0; i < n; i++) {
            scanf("%d",&t);
            sum += t;
            if( sum < small) small = sum;
        }
        printf("Scenario #%d: %lld\n", j, -1*small+1);
    }
}

The problem is simple. This solution takes 0.12 seconds on Spoj, though there are 0.01 second solutions. I am curious what optimizations may be done to this code to get faster. I thought -1*small+1 may be got using bit-wise operations but didn't find how. Also I can't get rid of long long since sum may exceed int.

Answer 1

You're making way too many I/O calls. Read the whole file at once, and then parse it, then create your output, and then write it all at once.