10进制换2进制

#include <iostream.h>
void main()
{
int sec(int n);
int i;
cout<<"请输入个10进制数:";
cin>>i;
cout<<"其2进制为:";
sec(i);
cout<<endl;
}
int sec(int n)
{
int i;
if (n!=0)
{
i = n%2;
sec(n/2);
cout<<i;
}
return i;
}