def main():
    x, y, h = map( int, input().split())
    x *= 1000
    y *= 1000
    ans = 0
    if x > y:
        x, y = y, x
    while x > h or y > h:
        if x <= h:
            x, y = y, x
        ans += 1
        y *= 2
        h *= 4
    print(ans)
    
if __name__ == '__main__':
    main()