g,c,p = map(int,input().split())
S = input()
G = S.count('G')
P = S.count('P')
C = S.count('C')
ans = 0
m = min(g,C)
ans += m
g -= m
C -= m
m = min(c,P)
ans += m
c -= m
P -= m
m = min(p,G)
ans += m
ans *= 3
p -= m
G -= m
m = min(p,P)
ans += m
p -= m
P -= m
m = min(c,C)
ans += m
c -= m
C -= m
m = min(g,G)
ans += m
g -= m
G -= m
print(ans)