View Code of Problem 27

#include "stdio.h"
#include "math.h"

void main()
{
	int a,b,i,j;
	int flag,sum,temp;
	for(;scanf("%d%d",&a,&b)!=EOF;)
	{
		
		if(a>b)
		{temp=a;a=b;b=temp;}
		sum=0;
		for(i=a+1;i<b;i++)
		{
			if(i==1)
			continue;									//1不是素数
			flag=0;
			for(j=2;j<=sqrt(i);j++)
			{
				if(i%j==0)
				{
					flag=1;
					break;
				}
			}
			if(flag==0)
				sum=sum+i;
		}
		printf("%d\n",sum);
	}

}