C++ Program to find if Entered Number is Prime

 #include<iostream>

using namespace std;

int main()

{

int i,n,flag=0;

cout<<"=========================================\n";

cout<<"Enter a number to check if is it a prime number or not\n";

cout<<"=========================================\n";

cout<<"Enter N : ";

cin>>n;

for(i=2;i<n-1;i++)

{

if(n%i==0)

{

flag++;

break;

}

}

if(flag==0)

{

cout<<"Its a prime number";

}

else if(flag!=0)

{

cout<<"It's not a prime number";

}

}