数学考试

传送门

#include <bits/stdc++.h>
using namespace std;

#define int long long

const int maxn = 2e5 + 10;
int t,n,k,a[maxn];

signed main(){
    ios::sync_with_stdio(0);
    cin.tie(0);cout.tie(0);
    cin >> t;
    while(t--){
        cin >> n >> k;
        for(int i = 1; i <= n; i++){
            cin >> a[i];
            a[i] += a[i - 1];
        }
        int pre = -2e10;
        int cnt = -2e10;
        for(int i = k; i + k <= n; i++){
            pre = max(pre,a[i] - a[i - k]);
            cnt = max(cnt,pre + a[i + k] - a[i]);
        }
        cout << cnt << endl;
    }
    return 0;
}