#include <iostream>

using namespace std;

int N, M, K, C, a, db, k;
int foglalt[11];

int keres(int a) {
    for(int i = 1; i <= N; ++i) {
        if(foglalt[i] <= a) {
            return i;
        }
    }

    return 0;
}

int main() {
    cin >> N >> K >> M >> C;
    for(int i = 1; i <= N; ++i) {
        foglalt[i] = 0;
    }

    for(int i = 1; i <= C; ++i) {
        cin >> a;
        k = keres(a);

        if(k != 0) {
            ++db;
            foglalt[k] = a + M;
        }
    }

    cout << db << '\n';
    return 0;
}