G0, C0, P0 = map(int, input().split())
S = str(input())
G1, C1, P1 = 0, 0, 0
for c in S:
    if c == 'G':
        G1 += 1
    elif c == 'C':
        C1 += 1
    else:
        P1 += 1
ans = 0
ans += min(G0, C1)*3
G0, C1 = G0-min(G0, C1), C1-min(G0, C1)

ans += min(C0, P1)*3
C0, P1 = C0-min(C0, P1), P1-min(C0, P1)

ans += min(P0, G1)*3
P0, G1 = min(P0, G1), G1-min(P0, G1)
if C1:
    if C0 >= C1:
        C0 -= C1
        ans += C1
        C1 = 0
    else:
        ans += C0
        C1 -= C0
        P0 -= C1
        C0 = 0
        C1 = 0
if P1:
    if P0 >= P1:
        P0 -= P1
        ans += P1
        P1 = 0
    else:
        ans += P0
        P1 -= P0
        G0 -= P1
        P0 = 0
        P1 = 0
if G1:
    if G0 >= G1:
        G0 -= G1
        ans += G1
        G1 = 0
    else:
        ans += G0
        G1 -= G0
        C0 -= G1
        G0 = 0
        G1 = 0
print(ans)