### Prime number between two intervals

I am trying to get prime numbers between two intervals. I have a function is_Prime to check if a number is prime or not and returns true or false. I have another function countPrimes to find prime numbers between two intervals using the is_Prime function.

When I input 12 20. The output I get is all the numbers between 12 and 20 instead of the prime numbers only.

 ``12345678910111213141516171819202122232425262728293031`` ``````#include using namespace std; int n, i; bool is_Prime(int n){ if (n < 2){ return false; } for (int i = 2; i < (n / 2 + 1); i++){ if (n % i == 0){ return false; } } return true; } int count_Primes(int x, int y){ while(bool is_Prime = 1) is_Prime++; } int main(){ int i; int x; cin >> x; int y; cin >> y; for(int i = x+1; i < y; ++i){ cout << i << endl; } return 0; }``````
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`while(bool is_Prime = 1)`What do you expect from this loop ?
Also you count_Primes doesn't return a value.
Maybe have a look in your textbook about functions and return values.

It would be much easier to use a for loop from x to y and call your is_Prime for each value. If it is a prime increment a counter. At the end of the function return the counter.
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