Prime generator

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What is your problem?

What don't you understand about it? Just giving you the answer won't help you learn.

In fact, I should chastise you for not attempting to write your own solution to the problem instead of just googling someone else's answer.

  #include <iostream>
#include <cmath>

using namespace std;

//function to check if the number is prime or not
int ifprime(int value){
  //if value is 1 or 0 simply return 0
  if(value == 1|| value == 0){
      return 0;
  }else if(value == 2){
    //if value is 2 then return 1
    return 1;
  }else{
    //use cmath for sqrt function
    for(int i=2; i<=sqrt(value); i++){
  		if((value%i) == 0){
        //if value is divisible by any other number return 0
  			return 0;
  		}
  	}
    //if value is not divisible by any other number return 1
    return 1;
  }

}

int main() {
	// your code here
  //we know that at a max there will be 10 test cases, so there will be 10 lowerlimits and upperlimits.
  //so I decided to use an array for lowerlimits and upperlimits
	int testcases,ll,ul,lowerlimit[11],upperlimit[11];

  //read the number of testcases
	cin>>testcases;
  cout<<endl;

  //for each test case, read the lower and upper limit and then assign them to the arrays
	for(int i=0;i<testcases;i++){
		cin>>ll>>ul;

    //store values in an array
    lowerlimit[i] = ll;
    upperlimit[i] = ul;

	}

  //for each test case
  for(int j = 0 ; j<testcases; j++){
    //read the lower limit and upper limit of that test case from the array
    int min = lowerlimit[j];
    int max = upperlimit[j];

    cout<<endl;

    //then for each value within the limit check if it is prime or not
    for(int k=min;k<=max;k++){
      //the if prime function is created above
       if(ifprime(k)){
         cout<<k<<endl;
       }
     }
  }

	return 0;
}