g,c,p = list(map(int, input().split()))
s = input()

aite_g = s.count("G")
aite_c = s.count("C")
aite_p = s.count("P")

ans=0

win = min(g,aite_c)
g-=win
aite_c-=win
ans+=win*3
win = min(c,aite_p)
c-=win
aite_p-=win
ans+=win*3
win = min(p,aite_g)
p-=win
aite_g-=win
ans+=win*3

ans+=min(g,aite_g)
ans+=min(c,aite_c)
ans+=min(p,aite_p)

print(ans)