常见小代码

1、斐波那契数列(两个元素的和确定下一个数)

# 1,1,2,3,5,8,13,21,34,55,89......
# 方法一：递归
def feb(n):
    if n == 1 or n == 2:
        return 1
    else:
        return feb(n-1)+feb(n-2)
n = 8
print(feb(n))


# 方法二：循环
x,y = 0,0
n = 8
for i in range(0,n+1):
    if i == 1 or i == 2:
        x,y = 1,1
    else:
        x,y = y,x+y
print(y)