from collections import Counter


def main():
    G, C, P = map(int, input().split())
    S = input()

    score = 0
    for other_hand in S:
        match other_hand:
            case "G":
                if P > 0:
                    score += 3
                    P -= 1
                elif G > 0:
                    score += 1
                    G -= 1
                else:
                    C -= 1
            case "C":
                if G > 0:
                    score += 3
                    G -= 1
                elif C > 0:
                    score += 1
                    C -= 1
                else:
                    P -= 1
            case "P":
                if C > 0:
                    score += 3
                    C -= 1
                elif P > 0:
                    score += 1
                    P -= 1
                else:
                    G -= 1

    print(score)


if __name__ == "__main__":
    main()