from collections import Counter

g1, c1, p1 = map(int, input().split())
s = Counter(input())
g2, c2, p2 = s['G'], s['C'], s['P']

ans = 0

# 勝ちに貪欲に割り当てる
d = min(g1, c2)
ans += 3 * d
g1 -= d
c2 -= d

d = min(c1, p2)
ans += 3 * d
c1 -= d
p2 -= d

d = min(p1, g2)
ans += 3 * d
p1 -= d
g2 -= d

# print(ans)
# print(g1, c1, p1)
# print(g2, c2, p2)

# あいこに貪欲に割り当てる
ans += min(g1, g2)
ans += min(c1, c2)
ans += min(p1, p2)


print(ans)