fn read() -> isize {
    let mut s = String::new();
    std::io::stdin().read_line(&mut s).ok();
    s.trim().parse::<isize>().unwrap()
}

fn gcd(a: isize, b: isize) -> isize {
    if b == 0 { return a; }
    gcd(b, a % b)
}

fn lcm(a: isize, b: isize) -> isize {
    if a ==0 && b == 0 {
        0
    } else {
        a / gcd(a, b) * b
    }
}

fn main() {
    let t = read();
    let u = read();
    let v = read();
    let l = lcm(lcm(t, u), v);
    let a = l / t;
    let b = l / u;
    let c = l / v;
    let g = gcd(a - b, a - c);
    let x = gcd(l, g);
    println!("{}/{}", l / x, g / x);
}