题解 2815: 求特殊自然数

解题思路:

注意事项:

参考代码:def switch_n(n,d):
   l = []
   while n > 0:
       l.append(str(n % d))
       n = n // d
   return "".join(l[::-1])

for i in range(81,1000):
   a = switch_n(i, 7)
   b = switch_n(i, 9)
   if len(a) == 3 and len(b) == 3 and a == b[::-1]:
       print(i)
       print(a)
       print(b)
       break