x,y,h = map(int,input().split())
x *= 1000
y *= 1000

C = 50
memo = [[0] * C for _ in range(C)]
stack = [(0,0)]
memo[0][0] = 1
while stack:
    yoko,tate = stack.pop()
    hh = h << (yoko + tate)
    if hh << yoko < y:
        if memo[yoko + 1][tate] == 0:
            memo[yoko + 1][tate] = 1
            stack.append((yoko + 1,tate))
    if hh << tate < x and memo[yoko][tate + 1] == 0:
        memo[yoko][tate + 1] = 1
        stack.append((yoko,tate + 1))
ans = 0
for i in range(C):
    for j in range(C):
        if memo[i][j] == 1 and (i + j) > ans:
            ans = i + j
print(ans)