#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef double db;
const ll N = 1e5 + 5;
ll n, k, ans, a[N];
db b[N];
bool check(double avg) {
    for (int i = 1; i <= n; i++) b[i] = b[i - 1] + a[i] - avg;
    db mi = 0;
    for (int i = k; i <= n; i++) {
        mi = min(mi, b[i - k]);
        if (i >= k && b[i] >= mi) return 1;
    } return 0;
}
int main() {
    scanf("%lld%lld", &n, &k);
    for (int i = 1; i <= n; i++) scanf("%lld", a + i);
    double l = 1, r = 1e9;
    for (int i = 0; i < 50; i++) {
        double mid = (l + r) / 2.0;
        if (check(mid)) l = mid;
        else r = mid;
    }
    printf("%.0lf", floor(l));
    return 0;
}