编程大作战 -- 挑战高考题

Python解法：

a = 1
b = 1
n = 1
while abs(b ** 2 / a ** 2 - 2) >= 0.01:
    b = b + 2 * a
    a = b - a
    n = n + 1
print(n) # 4

Scratch解法：