#include <bits/stdc++.h>
using namespace std;
const long long N = 1e5 + 10, mod = 1e9 + 7, inf = 1e18;
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  long long n, k, x, s = 0, flag = 0, ans = 0;
  cin >> n >> k;
  for (int i = 1; i <= n; i++) {
    cin >> x;
    s += x;
    if (s / k) flag = 0;
    ans += s / k;
    s %= k;
    if (flag) ans++, s = 0, flag = 0;
    if (s) flag = 1;
  }
  if (s) ans++;
  cout << ans;
  return 0;
}
