10490 - Mr. Azad and his Son!!!!!

[pingus]

Why WA ?

[c] Now, I get AC[/c]

Thank you , red Scorpion

[Red Scorpion]

Hi! Pingus.

I think your code is right.
I don't find anything wrong with your code!

[carneiro]

m should be :

unsigned long long int m;

as the problem says, it could be a 64 bit integer. long long int is 63 bit.

just change that and it should be accepted.

[Red Scorpion]

m should be :
unsigned long long int m;

Hi,
I got AC when using long long, so I think that's not the problem.

[Noim]

hi pingus,

are you sure you are getting WA for this program.
i got accepted using your program without changing anything.
Submit this program with o-matic page(http://acm.uva.es/problemset/submit.php)
and then observe the result.

may be WA for your mailing problem.

[Noim]

hi vega.marcin,

The output of your program is wrong when the input is 31.

[sumankar]

This is going to be a spoiler !
except for 11 23 and 29 i am calculating the rest
using the formula .
am i wrong ??

please help

[shamim]

there is a property associated with the formula which you can use to test all 31 cases, wiht no exceptions.

[babor]

Hai there is a very well known formula in "number theory ".

if p is a prime & 2^p -1 is a prime then (2^p-1)*(2^p -1 ) is a
perfect number . And this is the solution.
Thanks

[WR]

Hi, could somebody please explain problem 10490 to me?!

The OJ returns WA!

As I understood the problem the output is as follows
("n: " added for clarity)

2: Perfect: 6!
3: Perfect: 28!
5: Perfect: 496!
7: Perfect: 8128!
13: Perfect: 33550336!
17: Perfect: 8589869056!
19: Perfect: 137438691328!
31: Perfect: 2305843008139952128!

For any other input n (2 <= n <= 31) a perfect number does not exist!

Output is then either

"Given number is NOT prime! NO perfect number is available."

or

"Given number is prime. But, NO perfect number is available."

One can compute a perfect number from 2^(n-1) * (2^n - 1)
if (2^n - 1) is prime and n is prime (proof by Euclid, as far
as I know).

Well that equation holds for EVEN perfect numbers, but I don't really think
that's my problem (just a joke).

Probably one of my usual silly mistakes but where?

[osan]

in this problem u can get AC in short time by handle 6 perfect number as special case && primes less than 32.
)

[WR]

Thanks for the post Osan,

but the riddle remains.

1) If the formula from my original post is correct, then only
primes generate perfect numbers.

2) Considering the primes up to 31, 11, 23 and 29 are primes
that do not generate a perfect number.

So the output for all integers between 2 and 31 should be

Code: Select all

Perfect: 6!
Perfect: 28!
Given number is NOT prime! NO perfect number is available.
Perfect: 496!
Given number is NOT prime! NO perfect number is available.
Perfect: 8128!
Given number is NOT prime! NO perfect number is available.
Given number is NOT prime! NO perfect number is available.
Given number is NOT prime! NO perfect number is available.
Given number is prime. But, NO perfect number is available.
Given number is NOT prime! NO perfect number is available.
Perfect: 33550336!
Given number is NOT prime! NO perfect number is available.
Given number is NOT prime! NO perfect number is available.
Given number is NOT prime! NO perfect number is available.
Perfect: 8589869056!
Given number is NOT prime! NO perfect number is available.
Perfect: 137438691328!
Given number is NOT prime! NO perfect number is available.
Given number is NOT prime! NO perfect number is available.
Given number is NOT prime! NO perfect number is available.
Given number is prime. But, NO perfect number is available.
Given number is NOT prime! NO perfect number is available.
Given number is NOT prime! NO perfect number is available.
Given number is NOT prime! NO perfect number is available.
Given number is NOT prime! NO perfect number is available.
Given number is NOT prime! NO perfect number is available.
Given number is prime. But, NO perfect number is available.
Given number is NOT prime! NO perfect number is available.
Perfect: 2305843008139952128!

In my opinion that should be ok and the answer to the problem.

What do you mean by 6 perfect numbers as special cases?

[Sedefcho]

Hi, WR !

Your output seems OK to me.
Compare it once again with my output ( the output
from an ACC program ).


Just one question - what is your output for N=1 ?
I know they say N>1 but I handle the case N=1 too.


The output below is for an input file containing 32 lines.
On the first 31 lines I have the consequent numbers 1,2,3...,31.
On the 32nd line I have the number 0.

Code: Select all

Given number is NOT prime! NO perfect number is available.
Perfect: 6!
Perfect: 28!
Given number is NOT prime! NO perfect number is available.
Perfect: 496!
Given number is NOT prime! NO perfect number is available.
Perfect: 8128!
Given number is NOT prime! NO perfect number is available.
Given number is NOT prime! NO perfect number is available.
Given number is NOT prime! NO perfect number is available.
Given number is prime. But, NO perfect number is available.
Given number is NOT prime! NO perfect number is available.
Perfect: 33550336!
Given number is NOT prime! NO perfect number is available.
Given number is NOT prime! NO perfect number is available.
Given number is NOT prime! NO perfect number is available.
Perfect: 8589869056!
Given number is NOT prime! NO perfect number is available.
Perfect: 137438691328!
Given number is NOT prime! NO perfect number is available.
Given number is NOT prime! NO perfect number is available.
Given number is NOT prime! NO perfect number is available.
Given number is prime. But, NO perfect number is available.
Given number is NOT prime! NO perfect number is available.
Given number is NOT prime! NO perfect number is available.
Given number is NOT prime! NO perfect number is available.
Given number is NOT prime! NO perfect number is available.
Given number is NOT prime! NO perfect number is available.
Given number is prime. But, NO perfect number is available.
Given number is NOT prime! NO perfect number is available.
Perfect: 2305843008139952128!

[WR]

Thanks for the reply.

I've solved this problem half a year ago but forgot to post that.

Nevertheless, thanks for the attention.

[Rocky]

Yeh Sedefcho
You Are Right I do the Same & Got ACC..
Thanks.