Modified Kaprekar Numbers

Link:

　　https://www.hackerrank.com/challenges/kaprekar-numbers

 1 from __future__ import print_function

 2 

 3 

 4 def find_kaprekar(num):

 5 

 6     num_square = str(num ** 2)

 7 

 8     if len(num_square) == 1:

 9         if num == 1:

10             print (num, end = ' ')

11             return True

12     elif len(num_square) % 2 == 0:

13         d = len(num_square) / 2

14         if num == int(num_square[0:d]) + int(num_square[d:2*d]):

15             print (num, end = ' ')

16             return True

17     else:

18         d = len(num_square) // 2 

19         if num == int(num_square[0:d]) + int(num_square[d:(2*d+1)]):

20             print (num, end = ' ')

21             return True

22 

23 

24 

25 

26 def main():

27 

28     p = int(raw_input())

29     q = int(raw_input())

30 

31     have_kaprekar_num = False

32 

33     for i in xrange(p, q+1):

34         if find_kaprekar(i):

35             have_kaprekar_num = True

36 

37     if have_kaprekar_num == False:

38         print("INVALID RANGE")

39     else:

40         print()

41 

42 main()

 

//其他1

 1 def is_kaprekar(n):

 2     squared = str(n ** 2)

 3     mid = len(squared) - len(str(n))

 4     a = int(squared[mid:]) # 这种写法更简便

 5     b = int(squared[:mid]) if len(squared) > 1 else 0

 6     return a + b == n # 直接返回一个判断式子

 7 

 8 p = int(raw_input())

 9 q = int(raw_input())

10 

11 kaprekars = [str(x) for x in xrange(p, q + 1) if is_kaprekar(x)]

12 print ' '.join(kaprekars) if kaprekars else 'INVALID RANGE' # join函数的使用

 

//其他2

 1 import sys

 2 

 3 p = int(sys.stdin.readline())

 4 q = int(sys.stdin.readline())

 5 

 6 kaprekar = [1, 9, 45, 55, 99, 297, 703, 999, 2223, 2728, 4950, 5050, 7272, 7777, 9999, 17344, 22222, 77778, 82656, 95121, 99999] # 更省资源，因为数量不多，所以干脆一次性算出

 7 ans = [str(k) for k in kaprekar if k>=p and k<=q]

 8 if ans:

 9     print ' '.join(ans)

10 else:

11     print 'INVALID RANGE'