75分求条，互关

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

int main() {
    int n, m;
    cin >> n >> m;
    int a[400004];
    for (int i = 1; i <= n; i++) {
        cin >> a[i];
    }
    int maxa = 0, mina = 100000000;
    for (int i = 1; i <= n; i++) {
        maxa = max(maxa, a[i]);
		mina = min(mina, a[i]);
    }
    if (maxa == mina) {
        cout << 0;
    } else {
        cout << (maxa - mina - 1) / m + 1;
    }
    return 0;
}