INVALID POST

Thanks to Jeswin for pointing out bug in code.

:S :( Sheepish smile

## Monday, June 29, 2009

Subscribe to:
Post Comments (Atom)

skip to main |
skip to sidebar

Thoughts on Computers, Programming and OO Design.

Subscribe to:
Post Comments (Atom)

## 1 comment:

Just made a discovery!

For a problem on a sample space of cardinality up to 1229, it is possible to encode the information inside a 4-byte integer.

We can do it with prime number multiplication - the product is uniquely decomposable as everybody knows. The product of the first 1229 prime numbers fits within MAXINT!!!

The possibilities are endless....

- sonofdelphi

Absurd numerological coincidence :)

* Discovery made on 6/29. If 12/29 is divided by 6/29, the result is 2/1 !!!

Logical end of

Bus-Routes

Looking for a function

Code used to make the discovery

Hardly optimal. Stolen from the web and modified.

#include stdio.h

#include iostream

#include vector

using namespace std;

vector int anPrimes;

#define LIMIT 10000

void main()

{

int n=LIMIT,i=1,j,c;

unsigned int nProduct=1;

unsigned int nPrimeCount=0;

unsigned int nLastPrime = 0;

unsigned int nLastProduct = 0;

while(i<=n)

{

c=0;

for(j=1;j<=i;j++)

{

if(i%j==0)

c++;

}

if(c==2)

{

nProduct *= i;

if(nProduct > UINT_MAX)

break;

nPrimeCount++;

nLastPrime = i;

nLastProduct = nProduct;

}

i++;

}

cout "Last Prime : " nLastPrime endl;

cout "Prime Cardinal: " nPrimeCount endl;

cout "Product : " nProduct endl;

cout "MAXINT : " UINT_MAX endl;

getchar();

}

OUTPUT

Last Prime : 9973

Prime Cardinal: 1229

Product : 3975369062

MAXINT : 4294967295

Post a Comment