www.pudn.com > evil¡¯s illusion Server Codes.rar > prime.cpp

 
 
#include "stdafx.h" 
#include "prime.h" 
#include  
 
 
 
bool CPrime::IsPrime( int nNumber ) 
{ 
	int nSqr = (int) sqrt( nNumber ); 
 
	for ( int i = 2; i < nSqr; i++ ) 
	{ 
		if ( nNumber % i == 0 ) 
			return false; 
	} 
 
	return true; 
} 
 
 
int CPrime::RoundUp( int nNumber ) 
{ 
	while ( IsPrime( nNumber ) == false ) 
		++nNumber; 
 
	return nNumber; 
} 
 
 
int CPrime::RoundDown( int nNumber ) 
{ 
	while ( IsPrime( nNumber ) == false ) 
		--nNumber; 
 
	return nNumber; 
}