import java.util.*;

public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    int g1 = sc.nextInt();
    int c1 = sc.nextInt();
    int p1 = sc.nextInt();
    String s = sc.next();
    int g2 = 0;
    int c2 = 0;
    int p2 = 0;
    for(int i = 0; i < s.length(); i++) {
      if(s.charAt(i) == 'G') {
        g2++;
      } else if(s.charAt(i) == 'C') {
        c2++;
      } else {
        p2++;
      }
    }
    int ans = 0;
    int s1 = Math.min(g2, p1);
    ans += (3 * s1);
    g2 -= s1;
    p1 -= s1;

    int s2 = Math.min(c2, g1);
    ans += (3 * s2);
    c2 -= s2;
    g1 -= s2;

    int s3 = Math.min(p2, c1);
    ans += (3 * s3);
    p2 -= s3;
    c1 -= s3;

    int t1 = Math.min(g2, g1);
    ans += t1;
    g2 -= t1;
    g1 -= t1;

    int t2 = Math.min(c2, c1);
    ans += t2;
    c2 -= t2;
    c1 -= t2;

    int t3 = Math.min(p2, p1);
    ans += t3;
    p2 -= t3;
    p1 -= t3;

    System.out.println(ans);
  }
}