import math
H, A, D = map(int, input().split())
num = math.ceil(H/A)
res = float('inf')
for i in range(num+1):
    h = H-A*i
    if h<=0:
        res = min(res, num)
    else:
        res = min(res, i+math.ceil(h/D)*3/2)
print(res)