import java.util.Scanner;
public class Main {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
String a = sc.next();
int countA = 0;
int countB = 0;
for(int i = 0; i < a.length(); i++) {
if(a.charAt(i) == 'A') {
countA++;
}else if(a.charAt(i) == 'B') {
countB++;
}
}
System.out.println(countA + " : " + countB);
sc.close();
}
}