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Feb. 7th, 2013

Помните, я говорила про "Коровок", они же задачки USACO? Какие они милые и вообще.
Так вот, одну из них я просто обязана дать в качестве примера. Эта исключительно лёгкая, но вы посмотрите, какая прелесть же ж.

Superprime Rib

Butchering Farmer John's cows always yields the best prime rib. You can tell prime ribs by looking at the digits lovingly stamped across them, one by one, by FJ and the USDA. Farmer John ensures that a purchaser of his prime ribs gets really prime ribs because when sliced from the right, the numbers on the ribs continue to stay prime right down to the last rib, e.g.:

7 3 3 1

The set of ribs denoted by 7331 is prime; the three ribs 733 are prime; the two ribs 73 are prime, and, of course, the last rib, 7, is prime. The number 7331 is called a superprime of length 4.

Write a program that accepts a number N 1 <=N<=8 of ribs and prints all the superprimes of that length.

The number 1 (by itself) is not a prime number.
PROGRAM NAME: sprime
INPUT FORMAT
A single line with the number N.
SAMPLE INPUT (file sprime.in)

4

OUTPUT FORMAT
The superprime ribs of length N, printed in ascending order one per line.
SAMPLE OUTPUT (file sprime.out)

2333
2339
2393
2399
2939
3119
3137
3733
3739
3793
3797
5939
7193
7331
7333
7393

Restrictions:
One second runtime limit unless other specified (700 MHz Pentium III)
About 16MB datasize limit
About 1MB stacksize limit

Comments

( 2 comments — Leave a comment )
perelynn
Feb. 8th, 2013 03:28 pm (UTC)
Чувствую себя Ватсоном, впервые повстречавшим Шерлока Холмса.
dennyrolling
Feb. 8th, 2013 04:48 pm (UTC)
there are no superprimes longer than 8 digits.
( 2 comments — Leave a comment )