from collections import Counter

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

n = g + c + p
DP = [[[-1 for _ in range(p + 1)] for _ in range(c + 1)] for _ in range(g + 1)]
DP[g][c][p] = 0
for i in range(n):
    ss = s[i]
    res = n - i
    for j in range(g + 1):
        for k in range(c + 1):
            if 0 <= res - j - k <= p:
                l = res - j - k
                if ss == 'G':
                    if j > 0:
                        DP[j - 1][k][l] = max(DP[j - 1][k][l], DP[j][k][l] + 1)
                    if k > 0:
                        DP[j][k - 1][l] = max(DP[j][k - 1][l], DP[j][k][l])
                    if l > 0:
                        DP[j][k][l - 1] = max(DP[j][k][l - 1], DP[j][k][l] + 3)
                elif ss == 'C':
                    if j > 0:
                        DP[j - 1][k][l] = max(DP[j - 1][k][l], DP[j][k][l] + 3)
                    if k > 0:
                        DP[j][k - 1][l] = max(DP[j][k - 1][l], DP[j][k][l] + 1)
                    if l > 0:
                        DP[j][k][l - 1] = max(DP[j][k][l - 1], DP[j][k][l])
                else:
                    if j > 0:
                        DP[j - 1][k][l] = max(DP[j - 1][k][l], DP[j][k][l])
                    if k > 0:
                        DP[j][k - 1][l] = max(DP[j][k - 1][l], DP[j][k][l] + 3)
                    if l > 0:
                        DP[j][k][l - 1] = max(DP[j][k][l - 1], DP[j][k][l] + 1)
print(DP[0][0][0])