x,y,h = map(int,input().split())
h /= 1000
counter = 0
while h < x or h < y:
    if x <= y and x > h:
        x /= 2
        h *=2
        counter += 1
    elif x > y and y > h:
        y /= 2
        h *= 2
        counter += 1
    elif x <= y and y > h:
        y /=2
        h *= 2
        counter += 1
    elif x > y and x > h:
        x /=2
        h *=2
        counter += 1
    
print(counter)