Help with print function

[crozbme]

I am trying to change the default value in a print function so that n > len, however, when I do so, the output has garbage at the end of it. How do I properly get rid of the extra characters?

#include <iostream>
#include <assert.h>
#include <cstring>

using std::cout;
using std::endl;

class my_string
{
   public:
      my_string();
      my_string(const my_string& str);
      my_string(const char* p);
      ~my_string();
      int strcmp(const my_string& s1);
      void strrev();
      void print(int n = 0)const;
      int const Len();
      const char* gStr();

   private:
      char* s;
      int len;
};

my_string::my_string(): len(0),s (0){}

my_string::my_string(const char* p)
{
   len = strlen (p);
   s = new char[len + 1];
   assert(s != 0);
   strcpy(s, p);
}

my_string::my_string(const my_string& str):len(str.len)
{
   s = new char[len + 1];
   assert(s != 0);
   strcpy(s, str.s);
}

// Destructor
my_string::~my_string()
{
   delete [] s;
}

int const my_string::Len()
{
   return len;
}

const char* my_string::gStr()
{
   return s;
}

int main ()
{
   my_string string1("alibi"); 
      string1.print(); 
      string1.print(-1); 
      string1.print(3); 
      string1.print(23); 
      cout << "\n" << endl;

   
   my_string comp1("gladiator");
       if (comp1.strcmp ("gladiolus") < 0)
          cout << comp1.gStr() << " < " << "gladiolus" << endl;
       else if (comp1.strcmp ("gladiolus") == 0)
          cout << comp1.gStr() << " = " << "gladiolus" << endl;
       else
          cout << comp1.gStr() << " > " << "gladiolus" << endl;
          cout << "Original String: " << comp1.gStr() << " \nReversed String: ";
       comp1.strrev();
       comp1.print();
       cout << "\n" << endl; 
          
    my_string comp2("xyz"); 
       if (comp2.strcmp ("abcd") < 0)
          cout << comp2.gStr() << " < " << "abcd" << endl;
       else if (comp2.strcmp ("abcd") == 0)
          cout << comp2.gStr() << " = " << "abcd" << endl;
       else
         cout << comp2.gStr() << " > " << "abcd" << endl;
         cout << "Original String: " << comp2.gStr() << " \nReversed String: ";
       comp2.strrev();
       comp2.print();
       cout << "\n" << endl; 

    my_string comp3("same");
       if (comp3.strcmp ("same") < 0)
          cout << comp3.gStr() << " < " << "same" << endl;
       else if (comp3.strcmp ("same") == 0)
          cout << comp3.gStr() << " = " << "same" << endl;
       else
          cout << comp3.gStr() << " > " << "same" << endl;
          cout << "Original String: " << comp3.gStr() << " \nReversed String: ";
       comp3.strrev();
       comp3.print();
       cout << "\n" << endl; 
    
 system("PAUSE");
}

//Function that compares characters in a string

int my_string::strcmp(const my_string& s1)
{
   int i=0;
   while(s1.s[i] && s[i] && s1.s[i] == s[i])
   {
      i++;
   }
   return s1.s[i]-s[i];
}

//Function that reverses a given string 

void my_string::strrev()
{
   char* temp = new char[len + 1];
   int i = len -1;
   int j= 0;
   
   while (s[i])
   {
      temp[j++] = s[i--];
   }
   
   temp[j] ='\0';
   strcpy(s,temp);
   delete[] temp;
}

//Funtion that prints a string

void my_string::print(int n)const
{
   if (n < 0 || n > len)
      cout << "String Length Error!"; 
   else if (n == 0)
      n = len;
   for (int i = 0; i < n; i++)
        cout << s[i];
        cout << endl;  
}

[WaltP]

Can you try to give some details? Like where the problem is, what values are involved, what garbage characters. Without details we have no idea where to start since we didn't write the program.

[crozbme]

My problem is with this function:

void my_string::print(int n)const
{
   if (n < 0 || n > len)
      cout << "String Length Error!"; 
   else if (n == 0)
      n = len;
   for (int i = 0; i < n; i++)
        cout << s[i];
        cout << endl;  
}

The default n is set to 0 in a prior prototype.
I need to test a string when n > len so an error is prompted, however when test this bit of code:

my_string string1("alibi"); 
      string1.print(); 
      string1.print(-1); 
      string1.print(3); 
      string1.print(23); 
      cout << "\n" << endl;

string1.print(23);

outputs the error message plus random garbage.

alibi
String Length Error!
ali
String Length Error!alibi   ☻ ☻ ⌡ ⌐?K


gladiator > gladiolus
Original String: gladiator
Reversed String: rotaidalg


xyz < abcd
Original String: xyz
Reversed String: zyx


same = same
Original String: same
Reversed String: emas


Press any key to continue . . .

[WaltP]

Whether you have a good length or bad, you run the for loop outputting n characters of whatever happens to be in a