from collections import *
from itertools import *
from functools import *
from heapq import *
import sys,math
input = sys.stdin.readline

H,A,D = map(int,input().split())
E = [0]*(H+1)

for i in range(1,H+1):
    
    E[i] = min(1+E[max(0,i-A)],1.5+E[max(0,i-D)])
    
print(E[H])