here is my code;
#include
#include
using namespace std;
int main()
{
int t;
cin>>t;
while(t>0)
{
int a,b;
cin>>a>>b;
int s=b-a+1;
int arr[s];
for(int i=0;i<s;i++)
{
arr[i]=a+i;
}
int count=0;
for(int i=0;i<s;i++)
{
int f=0;
if(arr[i]!=2&&arr[i]!=0)
{
for(int j=2;j<=(sqrt(arr[i]));j++)
{
if(arr[i]%j==0){
f=1;
break;}
}
if(f==0)
count=count+1;
}
}
cout<<count<<endl;
t–;
}
return 0;
}