View Code of Problem 27

#include<stdio.h>
#include<math.h>
main()
{

	long int a,b,i,j,n;
	long int sum;
	while(scanf("%ld %ld",&a,&b)!=EOF)
	{
		sum=0;
		for(i=a+1;i<b;i++)
		{
			if(i==1||i==2||i==3)sum+=i;
			else if(i==4)continue;
			else{
			for(j=2;j<i;j++)
			{
				if(i%j==0)break;
			}
			if(j==i)sum+=i;
		}}
		printf("%ld\n",sum);
	}

	return 0;
}