def janken(G, C, P, S):
    p = 0
    S = list(S)
    for i in range(len(S)):
        if (S[i] == 'G') and (P > 0):
            P -= 1
            p += 3
            S[i] = 0
        elif (S[i] == 'C') and (G > 0):
            G -= 1
            p += 3
            S[i] = 0
        elif (S[i] == 'P') and (C > 0):
            C -= 1
            p += 3
            S[i] = 0
    for s in S:
        if s == 0:
            continue
        elif (s == 'G') and (G > 0):
            G -= 1
            p += 1
        elif (s == 'C') and (C > 0):
            C -= 1
            p += 1
        elif (s == 'P') and (P > 0):
            P -= 1
            p += 1
    return p

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

if __name__ == '__main__':
    main()