作业（吴童）

  1 s = 'python的创始人是Guido'
  2 print(s[11:])
  3 print(s[15:11:-1])
  4 print(s[::3])

  1 s1 = '你'
  2 s2 = '最帅'
  3 print(s1+s2)
  4 print(s1+s2*3)

  1 import random
  2 for i in range(10):
  3     a = random.randint(0,1000)
  4     x = a%10
  5     y = a//10
  6     z = a //100
  7     if x==y:
  8         print(a)
  9     if x==z:
 10         print(a)

  1 s = input('请输入一个字符串：')
  2 s1 = 0
  3 s2 = 0
  4 for i in s:
  5     if 'A'<=i<='z':
  6         s1+=1
  7     elif '0' <=i<='9':
  8         s2+=1
  9 print('字母的个数为{},数字的个数为{}'.format(s1,s2))

  1 for x in range(1,20):
  2     for y in range(1,33):
  3         z = 100-x-y
  4         if (z%3==0)and(5*x+3*y+z/3==100):
  5             print('公鸡{},母鸡{},小鸡{}'.format(x,y,z))

  1 year,month = eval(input('请输入一个年份：'))
  2 day= 1
  3 for i in range(year+1):
  4     if i >1990:
  5         if i % 4 ==0 and i %100 !=0 or i%400 ==0:
  6             day +=366
  7         else:
  8             day +=365
  9     else:
 10         continue
 11 for n in range(month):
 12     if n in [1,3,5,7,8,10,12]:
 13         day += 31
 14     elif n in [4,6,9,11]:
 15         day += 30
 16     elif n == 2:
 17         if year % 4 == 0 and year % 100 != 0 or year % 400 == 0 :
 18             day += 29
 19         else:
 20             day += 28
 21 f = day % 7
 22 print(f)