def main():
    g, c, p = map(int, input().split())
    s = input()
    g2 = s.count("G")
    c2 = s.count("C")
    p2 = s.count("P")

    ans = 0
    # win
    x, y, z = min(g, c2), min(c, p2), min(p, g2)
    ans += (x + y + z) * 3
    g -= x
    c2 -= x
    c -= y
    p2 -= y
    p -= z
    g2 -= z

    # drow
    ans += min(g, g2) + min(c, c2) + min(p, p2)

    print(ans)

if __name__ == '__main__':
    main()