【Python小试牛刀】循环

1、斐波那契数列

斐波那契数列，数列前两项为1，之后每一项都是前两项之和。

#!/usr/bin/env python3
a, b = 0, 1
while b < 100:
    print(b)
    a, b = b, a + b

默认print输出结果后会自动换行，如果不希望换行，只做间隔的话，就通过另一个参数end来替换这个换行符

print(a, end=' ')

2、幂级数。

写一个程序计算幂级数：e^x = 1 + x + x^2 / 2! + x^3 / 3! + ... + x^n / n! （0 < x < 1）。

#!/usr/bin/python3
x = float(input("Enter the value of x:"))

n = term = 1
result = 1.0
while n <= 100:
    term *= x/n
    result += term
    n += 1
    if term < 0.0001:
        break
print("No of Times={} and Sum = {}".format(n, result))

3、乘法表

打印10以内的乘法表。

#!/usr/bin/env python3
i = 1
print('-' * 60)
while i < 11
    n = 1
    while n <= 10:
        print("{:d}*{:d}={:d}".format(n, i, i * n), end=" ")
        n += 1
    print()
    i += 1
print('-' * 60)

• print('-' * 60)：一个字符串重复60次输出

4、打印星号

打印各种形状的星号

• 向上的直角三角

#!/usr/bin/env python3
n = int(input('Enter the number of rows:'))
i = 1
while i <= n:
    print('*' * i)
    i += 1

• 向下的直角三角

#!/usr/bin/env python3
n = int(input('Enter the number of rows:'))
i = n
while i > 0:
    x = '*' * i
    y = " " * (n - i)
    print(y + x)
    i -= 1

• 菱形

#!/usr/bin/env python3
n = int(input('Enter the number of rows:'))
i = 1
while i < n:
    x = '*' * (2 * i - 1)
    y = " " * (n - i)
    print(y + x)
    i += 1
while i > 0:
    x = " " * (n - i)
    y = '*' * (2 * i - 1)
    print(x + y)
    i -= 1

5、棍子游戏

有21根棍子，用户选1-4根棍子，然后电脑选1-4根棍子。谁选到最后一根棍子谁就输。（用户和电脑一轮选的棍子总数只能是5）

#!/usr/bin/env python3
sticks = 21

while True:
    print("Sticks left: ", sticks)
    sticks_token = int(input("Take sticks(1-4):"))
    if sticks == 1:
        print("Failed!")
        break
    if sticks_token >= 5 or sticks_token <= 0:
        print("Choose wrong number! continue:")
        continue
    print("computer took:", 5-sticks_token, "\n")
    sticks -= 5

注：结果是必输无疑，哈哈!