代码

#include <bits/stdc++.h>

using namespace std;

const int N = 1e5 + 10;
long long a[N]; 

int main() {
	long long n, k;
	scanf("%lld%lld", &n, &k);
	for (int i = 1; i <= n; i++) {
		scanf("%lld", &a[i]);
	}
	long long mx = -1;
	long long sum = 0;
	for (long long i = 1; i <= n-k+1; i++) {
		for (long long j = i; j <= k+i-1; j++) {
			sum += a[j];
		}
		if (mx < sum) {
			mx = sum;
		}
		sum = 0;
	}
	
	long long ret = floor((1.0 * mx) / k);
	printf("%lld\n", ret);
	
	return 0;
}

超时了，怎么优化？求完整代码！