gcp = list(map(int, input().split()))
s = input()

enemy = [0,0,0]
enemy[0] = s.count('G')
enemy[1] = s.count('C')
enemy[2] = s.count('P')

# 勝利回数
# グー,チョキ
NG = min(gcp[0], enemy[1])
gcp[0] -= NG
enemy[1] -= NG
# チョキ,パー
NC = min(gcp[1], enemy[2])
gcp[1] -= NC
enemy[2] -= NC
# パー,グー
NP = min(gcp[2], enemy[0])
gcp[2] -= NP
enemy[0] -= NP

# 引き分け回数
DG = min(gcp[0], enemy[0])
DC = min(gcp[1], enemy[1])
DP = min(gcp[2], enemy[2])

print(3*(NG+NC+NP)+1*(DG+DC+DP))