View Code of Problem 27

#include <stdio.h>
#include <math.h>
int main(){
  int a,b;
  int i,j,flag;
  int sum,temp;
  while (scanf("%d%d",&a,&b) != EOF){
	  if(a>b){
		  temp=a;
		  a=b;
		  b=temp;
	  }
	  sum=0;
    for(i=a+1;i<b;i++){
      flag=1;
      if(i==1)
        flag=0;
      else{
		  for(j=2;j<=sqrt(i);j++){
			if(i%j==0){
            flag=0;
			break;
			}
      }
      
    }
	  if(flag==1)
        sum+=i;
      
    
    
    
  }
  printf("%d\n",sum);
  
  }
  
  
  return 0;


}