public class Main {
    public static void main(String[] args) {
        System.out.println(elimina("PUO#C MIP#NO#AS"));
    }
 
    public static String elimina(String frase) {
        StringBuilder sb = new StringBuilder(frase.length());
        for (int j = 0; j < frase.length(); j++) {
            if (frase.charAt(j) == '#') {
                sb.deleteCharAt(sb.length() - 1);
            } else {
                sb.append(frase.charAt(j));
            }
        }
        return sb.toString();
    }
}

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