import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int g = sc.nextInt();
        int c = sc.nextInt();
        int p = sc.nextInt();
        int gCount = 0;
        int cCount = 0;
        int pCount = 0;
        for (char cc : sc.next().toCharArray()) {
            if (cc == 'G') {
                gCount++;
            } else if (cc == 'C') {
                cCount++;
            } else {
                pCount++;
            }
        }
        int ans = 0;
        int x = Math.min(g, cCount);
        ans += x;
        g -= x;
        cCount -= x;
        int y = Math.min(c, pCount);
        ans += y;
        c -= y;
        pCount -= y;
        int z = Math.min(p, gCount);
        ans += z;
        p -= z;
        gCount -= z;
        ans *= 3;
        ans += Math.min(g, gCount);
        ans += Math.min(c, cCount);
        ans += Math.min(p, pCount);
        System.out.println(ans);
    }
}