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C++ = Code to check number is a prime or not. If not find the nearest prime number.

Code: 
#include <iostream>
using namespace std;
bool prime(int n)
{
if (n<=1)
{
return false;
}

       for (int i=2;i<=n/2;i++)
   {
      if (n%i==0)
  {
  return false;
  }
   }    
    return true;
}

int nearest(int n)
{
for (int i=n-1;i>=2;i--)
{
if (prime(i))
{
return i;
}
}
return 0;
}

int main ()
{
int number;
cout<<"Enter any number : ";
cin>>number;
if (prime(number))
{
cout<<"The number is prime. "<<endl;
}
    else
    {
    cout<<"The entered number is compositive."<<endl;
    cout<<"The nearest prime number will be "<<nearest(number)<<endl;
}

}
Result:



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