fn main() {
    let mut s = String::new();
    std::io::stdin().read_line(&mut s).ok();
    let v: Vec<i32> = s.trim().split_whitespace().map(|e| e.parse::<i32>().unwrap()).collect();

    let a = v[0];
    let b = v[1];
    let c = v[2];
    let d = v[3];

    let mut ans = 0;
    for i in 1..=a {
        let m = c * i;
        if i + m <= d && m <= b {
            ans = i;
        }
    }
    println!("{}", ans);
}