#include <iostream>
int main() {
    int data[4];
    int i = 0;
	int l;
    while (std::cin >> l) {
        data[i] = l;
        i++;
    }
    int vega = data[0];
    int meet = data[1];
    int levaledge = data[2];
    int limit = data[3];
    int r;
    for (r = 0; r <= vega; r++) {
        if ((r + r * levaledge) > limit) {
            if (r > 0) r--;
            std::cout << r << std::endl;
            break;
        }
    }
    std::cout << r << std::endl;
}