g,c,p = list(map(int, input().split()))
hands=[c,g,p]
s = input()
ans=0
te="CGPCGP"

for i in range(len(s)):
    draw = te.find(s[i])
    win = (te.find(s[i])+1)%3
    lose = (te.find(s[i])+2)%3

    if hands[win] > 0:
        hands[win]-=1
        ans+=3
    elif hands[draw] > 0:
        hands[draw]-=1
        ans+=1
    else:
        hands[lose]-=1

print(ans)