CCC '00 J2 - 9966

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Points: 3
Time limit: 2.0s
Memory limit: 16M

Problem type

Canadian Computing Competition: 2000 Stage 1, Junior #2

The digits 0, 1, and 8 look much the same if rotated 180 degrees on the page (turned upside down). Also, the digit 6 looks much like a 9, and vice versa, when rotated 180 degrees on the page. A multi-digit number may also look like itself when rotated on the page; for example 9966 and 10801 do, but 999 and 1234 do not.

You are to write a program to count how many numbers from a given interval look like themselves when rotated 180 degrees on the page. For example, in the interval [1 \dots 100] there are six: 1, 8, 11, 69, 88, and 96.

Your program should take as input two integers, m and n, which define the interval to be checked, 1 \le m \le n \le 32000. The output from your program is the number of rotatable numbers in the interval.

You may assume that all input is valid.

Sample Input


Sample Output



  • -25
    Raymond2031  commented on March 11, 2018, 9:58 a.m.

    Ricegum is the goat

    • 1
      662123  commented on Aug. 2, 2018, 12:43 p.m.

      really cuz??