Prime visits challenge

#1

please check the code…please tell me why its not working for other test cases
#include
using namespace std;
int main() {
int N;
cin>>N;
for(int i=0;i<N;i++)
{
int a=0;
int b=0;
cin>>a>>b;
if(a==1)
{
a++;
}

int count=0;
int flag=1;
for(int j=a;j<=b;j++)
{
    
for(int i=2;i<j;i++)
{
    if(j%i!=0)
    {
       flag=1;

    }
    else
    {
        //cout<<" for u";
        flag=0;
        break;
    }
}
  if(flag==1)
 {
     //cout<<"hello"<<" ";
    count++;
  }
  else
  {
   //cout<<" aaja aaja";
  }
}
cout<<count<<endl;
}
return 0;

}

#2

Hello @ashnagalhotra,

Always Share your code using Online Coding Blocks IDE.
The way you have shared it may introduce many run-time error to it.
STEPS:

  1. Paste it at https://ide.codingblocks.com/
  2. Save your code there
  3. Share the URL generted

Now, coming back to our code:
As, the value of a and b can be anything in the range [1,1000000].
For the cases like a=1 and b=1000000,
Your code will face TLE.

Reason:
Time complexity of your code is O(Nbb) which is very high.

Solution:
Rather use prime sieves method to solve this problem.

Hope, this would help.
Give a like if you are satisfied.

#3

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