use std::io;

fn main() {
    let mut input = String::new();
    io::stdin().read_line(&mut input)
        .expect("Read Error");
    let numbers: Vec<i64> = input.split_whitespace()
        .map(|w| w.parse().unwrap())
        .collect();

    println!("{}", solve(numbers[0],  numbers[1], numbers[2], numbers[3]));
}

fn solve(a: i64, b: i64, c: i64, d: i64) -> i64 {
    (a % d) * (b % d) % d * (c % d) % d
}