use itertools::Itertools;
use proconio::{input, marker::Chars};
fn main() {
    input! {
        n: usize,
        m: usize,
        mut s: Chars,
        t: String,
    }
    if t == "Warong" {
        for i in 0..m {
            s[i] = 'A';
        }
        if s.iter().all(|&c| c != 'W') && s.iter().filter(|&&c| c == '?').count() == 1 {
            for i in 0..n {
                if s[i] == '?' {
                    s[i] = 'W';
                }
            }
        }
    }
    // not AAA.. || not any(W)
    if t == "NotWarong" {
        // AAA.., not any(W) 
        if s[..m].iter().all(|&c| c == 'A') {
            for i in m..n {
                if s[i] == '?' {
                    s[i] = 'A';
                }
            }
        }
        // not AAA.., any(W) 
        if s[m..].iter().any(|&c| c == 'W') && s[..m].iter().all(|&c| c != 'W') && s[..m].iter().filter(|&&c| c == '?').count() == 1 {
            for i in 0..m {
                if s[i] == '?' {
                    s[i] = 'W';
                }
            }
        }
    }
    println!("{}", s.iter().join(""));
}