1.判断闰年

if __name__ == '__main__':

# 1.能被400整除的年份

# 2.能被4整除，但是不能被100整除的年份

# 3.以上2种方法满足一种即为闰年

year = input("请输入年份：")

if year.isdigit() and len(year) == 4:

year = int(year)

if year % 400 == 0 or (year % 4 == 0 and year % 100 != 0):

# print("您输入的%s是闰年！" % year)

print("您输入的{}是闰年！".format(year))

else:

# print("您输入的%s是平年！" % year)

print("您输入的{}是平年！".format(year))

else:

print("输入有误，请重新输入：")

2. 乘法表

if __name__ == '__main__':

# for i in range(1, 10):

# for j in range(1, 10):

# if j <= i:

# print(i, "*", j, "=", i*j, end = " ")

# print("\n")

# //

# for i in range(1, 10):

# for j in range(1, 10):

# if j <= i:

# print('{}*{}={}'.format(i, j, i * j), end='\t')

# j+=1

# print('\n')

# i+=1

# //

# for i in range(1, 10):

# for j in range(1, 10):

# if j <= i:

# print('%s * %s = %s' % (i, j, i * j), end='\t')

# print()

# //

# for i in range(1, 10):

# for j in range(1, i+1):

# print(str(i) + '*' + str(j) + '=' + str(i*j), end='\t')

# print()

for i in range(9, 0, -1):

for j in range(9, 0, -1):

if j <= i:

print('%s * %s = %s'% (i, j, i * j), end='\t')

print()

# //

# i = 1

# while i <= 9:

# j = 1

# while j <= i:

# print(i, "*", j, "=", i*j, end = " ")

# j += 1

# print("\n")

# i += 1

# i = 1

# while i <= 9:

# j = 1

# while j <= i:

# print('{}*{}={}'.format(i, j, i * j), end='\t')

# j += 1

# print('\n')

# i += 1

3.打印三角形

if __name__ == '__main__':

# num = int(input("请输入个数："))

# i = 1

# while i <= num:

# j = 1

# while j <= i:

# print("*", end = " ")

# j += 1

# print("\n")

# i += 1

num = int(input("enter a num: "))

for i in range(1, num):

for j in range(1, num):

if j <= i:

print("*", end = " ")

print("\n")