def getpoint(p, r, point, prod):
	ap = r if p >= r else p
	p -= ap
	r -= ap
	return p, r, point + prod*ap
G, C, P = map(int,raw_input().split(" "))
S = list(raw_input())
rG = S.count("G")
rC = S.count("C")
rP = S.count("P")
point = 0
G, rC, point = getpoint(G, rC, point, 3)
C, rP, point = getpoint(C, rP, point, 3)
P, rG, point = getpoint(P, rG, point, 3)
G, rG, point = getpoint(G, rG, point, 1)
C, rC, point = getpoint(C, rC, point, 1)
P, rP, point = getpoint(P, rP, point, 1)
print point