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筛法也超时??只有6个0啊~~哪位高手帮忙看看啊~~

Posted by ding59 at 2008-10-20 10:36:40 on Problem 2262
#include<stdio.h>
#include<string.h>
#define max 1000000
int sieve[max+1];
int pr[max+1];
int count;
#define del 1
#define kep 0
void in(int  n)
{		
	int i,k,c=1;	
	int	prime=2;
	pr[0]=2;
	count=0;
	for(i=0;i<=n;i++)
		sieve[i]=kep;
	for(i=0;i<=n&&prime<=n;i++)
		{
			if(sieve[i]==kep)
			{
				prime=i+i+3;
				pr[c++]=prime;
				count++;
				for(k=prime+i;k<=n;k+=prime)
					sieve[k]=del;
			
		}
	
	}	
}
void main()
{
	int n,i,a,b,j,flag;
	while(scanf("%d",&n),n)
	{
		memset(pr,0,sizeof(pr));
		flag=0;
		in(n);
     for(i=0;i<count;i++)
	 {
		 for(j=count-1;j>=0;j--)
		 {
			 if(n==(pr[i]+pr[j]))
			 {
				 a=pr[i];
				 b=pr[j];
				 flag=1;
				 break;
			 }
		 }
		 if(flag)
			 break;
	 }
	 if(flag)
	 printf("%d = %d + %d\n",n,a,b);
	 else printf("Goldbach's conjecture is wrong.\n");
	}			
}


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