use proconio::input;

fn main() {
    input! {
        r: usize,
        p: usize,
        q: usize,
        a: usize,
        b: usize,
        c: usize,
        d: usize,
    }
    let mut left = 0;
    let mut right = 1_000_000_000_usize + 1;
    while right - left > 1 {
        let mid = (left + right) / 2;

        let is_enough_coder = 3 * mid <= a + b + c + d;

        let need_to_change = mid.saturating_sub(a) + mid.saturating_sub(b) + mid.saturating_sub(c);
        let is_enough_rate = mid * p + need_to_change * q <= r;

        if is_enough_coder && is_enough_rate {
            left = mid;
        } else {
            right = mid;
        }
    }

    println!("{}", left);
}