CCC '00 J2 - 9966 - Olympiads Online Judge

CCC '00 J2 - 9966

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Points: 3 (partial)

Time limit: 1.0s

Memory limit: 256M

Problem type

Canadian Computing Competition: 2000 Stage 1, Junior #2

The digits $0$ ~0~, $1$ ~1~, and $8$ ~8~ look much the same if rotated $180$ ~180~ degrees on the page (turned upside down). Also, the digit $6$ ~6~ looks much like a $9$ ~9~, and vice versa, when rotated $180$ ~180~ degrees on the page. A multi-digit number may also look like itself when rotated on the page; for example $9966$ ~9966~ and $10\,801$ ~10\,801~ do, but $999$ ~999~ and $1234$ ~1234~ do not.

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

Your program should take as input two integers, $m$ ~m~ and $n$ ~n~, which define the interval to be checked, $1 \le m \le n \le 32\,000$ ~1 \le m \le n \le 32\,000~. The output from your program is the number of rotatable numbers in the interval.

You may assume that all input is valid.

Sample Input

1
100

Sample Output

Comments

0

MonkeyKang16 commented on Sept. 6, 2025, 4:48 p.m.

for this its a good idea to use min and max to convert your 2 varibles like this for example
your varible name here = min(n, m)
your other varible name here = max(n, m)

0

Chris_Shang commented on Oct. 5, 2025, 3:04 p.m.

thanks

1

d commented on June 8, 2025, 11:18 p.m.

Sequence for this problem https://oeis.org/A000787