View Code of Problem 27

#include<iostream>
#include<math.h>
using namespace std;
bool sushu(int n)
{   int flag=0;
	for(int i=2;i<=sqrt(n);i++)
	{
		if(n%i==0) flag++;
	}
	if(flag==0) return true;
	 else return false;	
}
int main()
{
	long long  a,b,sum;
	while(cin>>a>>b)
	{  
	   if(a>b) swap(a,b);
	   sum=0;
		for(long long  int i=a+1;i<b;i++)
		{
			if(sushu(i))
			sum=sum+i;
		}
		cout<<sum<<endl;
	}
 }