import sys

x,y,h = map(int, sys.stdin.readline().strip().split())

count = 0

x = x * 100 * 10
y = y * 100 * 10

def yoko():
    global x,h,count
    x = x / 2
    h = h * 2
    count += 1

def tate():
    global y,h,count
    y = y / 2
    h = h * 2
    count += 1


while True:
    if h > 1000:
        break
    if x >= 2 and x > h:
        yoko()
    elif y >= 2 and y > h:
        tate()
    else:
        break

print(count)