from functools import lru_cache
@lru_cache(maxsize=10000)
def f(x):
    if x <= 0:
        return 0
    ret = 0
    ret += min(1 + f(x - A), 3 / 2 + f(x - D))
    return ret

H, A, D = map(int, input().split())
print(f(H))