#include <bits/stdc++.h>
using namespace std;
int N, K, a[100000], parsum1[100001], parsum2[100001];
long long ans = 0;
int main() {
  cin >> N >> K;
  for (int i = 0; i < N; ++i) cin >> a[i];
  long long sum1 = 0, sum2 = 0;
  for (int i = 1; i <= N; ++i) {
    sum1 += a[i - 1];
    parsum1[i] = sum1;
    if (a[i - 1] >= 0) sum2 += a[i - 1];
    parsum2[i] = sum2;
  }
  long long lsum = 0, csum = 0, rsum = 0;
  for (int i = 0; i < N - K; ++i) {
    csum = max(0, parsum1[i + K] - parsum1[i + 1]);
    lsum = parsum2[i];
    rsum = parsum2[N] - parsum2[i + K];
    ans = max(ans, lsum + csum + rsum);
    cout << lsum << "+" << csum << "+" << rsum << "=" << lsum + csum + rsum
         << endl;
  }
  cout << ans << endl;
}
