a.cpp

acm大赛题

#include <stdio.h>

int main(void)
{
	int num,i,j,temp,numtemp;
	bool *p;
	
    freopen("A.in","r",stdin);
	freopen("A.out","w",stdout);

	p = new bool[1000000];
	for(i=1;i<1000000;i++)
		p[i]=1;
	p[1]=0;
	for(i=2;i<1000;i++)
		if(p[i]==1)
			for(j=i+1;j<1000000;j++)
			{
				if(p[j]==1)
					if((j%i)==0)
                        p[j]=0;
			}
	while(scanf("%d",&num) != EOF)
	{
       if (num == 0)
            break;	
       numtemp=num;
		while(1)
		{
			if(num<10&&p[num]==0)
			{
				printf("%7d    none\n",numtemp);
				break;
			}
			else
			if(p[num]==1)
			{
				printf("%7d %7d\n",numtemp,num);
				break;
			}
			else
			{
				temp=0;
				while(num!=0)
				{
					temp+=num%10;
					num/=10;
				}
				num=temp;
			}

			
		}
    }

	return 0;
}