3实例

• 乘法口诀

#!/usr/local/bin/python3.6
def ff(n):
    for i1 in range(1, n + 1):
        for i2 in range(1, i1 + 1):
            print('%s*%s=%s' % (i1, i2, i2 * i1), end=' ')
        print()

ff(9)

• 阶乘

#!/usr/local/bin/python3.6
def jiec(n):
        if n == 1:
                return 1
        else:
                return n * jiec(n-1)
print(jiec(5))

• 斐波那契数列

#!/usr/local/bin/python3.6
import sys
def fbnq(n):
        if n < 1:
                return -1
        if n == 1 or n == 2:
                return 1
        else:
                return fbnq(n-1) + fbnq(n-2)
i = fbnq(int(sys.argv[1]))
if i != -1:
        print(i)

• 汉诺塔

#!/usr/local/bin/python3.6
def hnt(n, x, y, z):
        if n == 1:
                print(x, '--->', z)         ##如果只有一层，那么直接从x拿到z
        else:
                hnt(n-1, x, z, y)           ##n-1 ，将x拿到y上面，用z来过度
                print(x, '--->', z)         ##把最后一层拿到z
                hnt(n-1, y, x, z)           ##此时都在y上面，将y以x为过度拿到z
i = 3
hnt(i, 'X', 'Y', 'Z')