#include <bits/stdc++.h>
using namespace std;
long long const delta = 1000000007;
int main() {
  std::ios::sync_with_stdio(0);
  ;
  cin.tie(0);
  cout.tie(0);
  long long n, k;
  cin >> n >> k;
  long long dp[n], a[n], sum[n];
  long long ans = delta;
  for (long long i = 0; i < n; i++) {
    cin >> a[i];
    dp[i] = 0;
    sum[i] = 0;
    sum[i] += a[i];
    if (i) sum[i] += sum[i - 1];
    dp[i] += sum[i];
    if (i - k >= 0) dp[i] -= sum[i - k];
  }
  long long ind = delta;
  for (long long i = k - 1; i < n; i++) {
    if (dp[i] < ans) {
      ans = dp[i];
      ind = i - k + 1;
    }
  }
  cout << ++ind;
  return 0;
}
