#include <iostream>

using namespace std;

int main()
{
    int N, K, L, F;
    int parSum[100001] = {};
    int temp, nrAlarm = 0;
    bool isAlarm = false;

    cin >> N >> K >> L >> F;
    for(int i = 1; i <= N; i++){
        cin >> temp;
        parSum[i] = parSum[i-1] + temp;
        if(i >= K && 1.0*(parSum[i] - parSum[i-K])/K > F && !isAlarm){
            isAlarm = true;
            nrAlarm++;
            continue;
        }
        if(i >= L && 1.0*(parSum[i] - parSum[i-L])/L < F && isAlarm){
            isAlarm = false;
        }
    }
    cout << nrAlarm << endl;
    return 0;
}