#!/usr/bin/env python
# -*- coding: utf-8 -*-

hand_num = list(map(int,input().split()))
hand = {'G':0,'C':1,'P':2}

S = input()
point = 0
for s in S:
    if hand_num[(hand[s] + 2)%3]  > 0:
        hand_num[(hand[s] + 2)%3] -= 1
        point += 3
    elif hand_num[hand[s]] > 0:
        hand_num[hand[s]] -= 1
        point += 1
    else:
        hand_num[(hand[s] + 1)%3] -= 1
print(point)