#!/usr/bin/env python3


def maximize(x, y, h):
    if x > y:
        x, y = y, x
    res = 0
    while x > h:
        x /= 2
        h *= 2
        res += 1
    while y > h:
        y /= 2
        h *= 2
        res += 1
    return res


def main():
    x0, y0, h = (int(z) for z in input().split())
    x = 1000 * x0
    y = 1000 * y0
    res = maximize(x, y, h)
    print(res)


if __name__ == "__main__":
    main()