// Program 72: Decode ASCII Values from a Continuous String

import java.util.*;
class DecodeAscii {
    static boolean valid(int n) {
        return n == 32 || (n >= 65 && n <= 90) || (n >= 97 && n <= 122);
    }
public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    String s = sc.nextLine().trim();
    if (!s.matches("[0-9]+")) {
        System.out.println("INVALID INPUT");
        return;
    }
StringBuilder out = new StringBuilder();
int i = 0;
while (i < s.length()) {
    int code = -1, len = 0;
    for (int size = 3; size >= 2; size--) {
        if (i + size <= s.length()) {
            int value = Integer.parseInt(s.substring(i, i + size));
            if (valid(value)) {
                code = value;
                len = size;
                break;
            }
    }
}
if (code >= 0) {
    out.append((char) code);
    i += len;
}
else {
    i++;
}
}
System.out.println(out);
}
}