C++ Program to Print All Prime Numbers Between 1 to N

  • Write a C++ program to print all Prime numbers between 1 to 100.
  • How to find all Prime numbers between 1 to N.

C++ program to print all prime numbers between 1 to N

#include<iostream>

using namespace std;
  
int main(){
  
    int N, i, j, isPrime, n;

    cout << "Enter the value of N\n";
    cin >> N;
  
    // For every number between 2 to N, check 
    // whether it is prime number or not 
     
    for(i = 2; i <= N; i++){
        isPrime = 0;
        // Check whether i is prime or not
        for(j = 2; j <= i/2; j++){
             // Check If any number between 2 to i/2 divides I 
             // completely If yes the i cannot be prime number
             if(i % j == 0){
                 isPrime = 1;
                 break;
             }
        }
          
        if(isPrime==0 && N!= 1)
            cout << i << " ";
    }

   return 0;
}
Output
Enter the value of N
50
2 3 5 7 11 13 17 19 23 29 31 37 41 43 47