import sys 
def main():
    x,y,h = map(int,sys.stdin.readline().split())
    x *= 1000
    y *= 1000
    ans = 0
    while x > h or y > h:
        if x > h:
            ans += 1
            h *= 2
            x /= 2
        if y > h:
            ans += 1
            h *= 2
            y /= 2
    print(ans)
if __name__ == '__main__':
    main()