#include
using namespace std;
int KTSNT(int n)
{
if(n<2)
return false;
for(int i=2; i<=n/2; i++)
if(n%i==0)
return false;
return true;
}

int main()
{
int n;
cout<<“Nhap vao so nguyen duong n: “;
cin>>n;
if(KTSNT(n)==true)
cout<< n << " la so nguyen to!”;
else
cout<< n <<” khong la so nguyen to!";
cout<<endl;
}
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