1.输入一个整数，显示其所有的素数因子
n = int (input('请输入一个数：'))
for i in range(2,n):
for j in range(2,i):
if i%j==0:
break
else:
print(i)
2.输入年份及 1-12月份，判断月份属于大月、小月、闰月、平月，并输出本月天数
year = int(input('请输入需要判断的年份：'))
month = int(input('请输入月份：'))
if year % 4 == 0 and year % 100 != 0 or year % 400 == 0:
print(year, '是闰年')
f = 1
else:
print(year, '是平年')
f = 0
if month == 1 or month == 3 or month == 5 or month == 7 or
month == 8 or month == 10 or month == 12:
print(year, '年', month, '月有31天,是小月')
elif month == 4 or month == 6 or month == 9 or month == 11:
print(year, '年', month, '月有30天，是大月')
elif month == 2 and f == 1:
print(year, '年', month, '月有29天，是闰月')
elif month == 2 and f == 0:
print(year, '年', month, '月有28天，是平月')
else:
print('输入的年份和月份有误！')
3.输入三个整数，按升序输出
num1 = int(input('请输入第一个整数：'))
num2 = int(input('请输入第二个整数：'))
num3 = int(input('请输入第三个整数：'))
if num1 > num2 and num1 > num3 and num2 > num3:
print(num1, num2, num3)
elif num1 > num2 and num1 > num3 and num3 > num2:
print(num1, num3, num2)
elif num2 > num1 and num2 > num3 and num1 > num3:
print(num2, num1, num3)
elif num2 > num1 and num2 > num3 and num3 > num1:
print(num2, num3, num1)
elif num3 > num1 and num3 > num2 and num2 > num1:
print(num3, num2, num1)
elif num3 > num1 and num3 > num2 and num1 > num2:
print(num3, num1, num2)
