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

int n, k, a, b, dp[500010], ans;

int main(){
    ifstream cin ("divk.in");
    ofstream cout ("divk.out");
    cin >> n >> k >> a >> b;
    for (int i=1; i<=n; i++) cin >> dp[i], dp[i] += dp[i-1];
    for (int i=a; i<=n; i++){
        for (int j=max(0, i - b); i - j >= a; j++){
            if ((dp[i] - dp[j])%k == 0) ans++;
        }
    }
    cout << ans;
    return 0;
}