fn main() {
    let mut abcd = String::new();
    std::io::stdin().read_line(&mut abcd).ok();
    let abcd: Vec<isize> = abcd.trim().split_whitespace().map(|s| s.parse().unwrap()).collect();
    let a = abcd[0];
    let b = abcd[1];
    let _c = abcd[2];
    let d = abcd[3];

    if d >= 10 {
        println!("Impossible");
    } else {
        let mut result: isize = 0;
        result += if b > 100 { 5000 } else if a + b > 100 { 50*b + (100-b)*100 } else { 50*b + 100*a };
        for i in 101..=(a+b) {
            let multi: u32 = ((i-1) / 100) as u32;
            let multi: isize = 2i32.pow(multi) as isize;
            result += multi * if i <= b { 50 } else { 100 };
        }
        println!("Possible");
        println!("{}", result);
    }
}