Program to illustrates Recursion in c++

    #include <iostream.h>
    int addition ( int n ) ;
    void main ()
    {
        int n ;
        cout<< "\n Input n : ";
        cin >> n;
        if ( n <= 0 )
            cout<< "\n Number should be greater than zero !!!";
        else
            cout<< "\n Sum of 1 to "<<n<< " = "<< addition ( n ) ;
    }
    int addition ( int n )
    {
        if ( n == 1 )
            return ( 1 ) ;
        else
            return ( n + addition ( n - 1 ) ) ;
    }