strcmp problem

Hey all I am having a problem with this bit of code if someone would like to help!
The problem is it will crash when the last names are the same. Any help on this?

  bool LessThanByName( const Passenger & passenger ) const
   {
      char last0[MAX_LENGTH + 1];
      char last1[MAX_LENGTH + 1];
      char first0[MAX_LENGTH + 1];
      char first1[MAX_LENGTH + 1];
      
      for(int i = 0; i < last[i]; i++)
      {
         last0[i] = last[i];
     }   
      for(int i = 0; i < passenger.last[i]; i++)
      { 
        last1[i] = passenger.last[i];
      }
      for(int i = 0; i < first[i]; i++)
      {   
         first0[i] = first[i];
      }
      for(int i = 0; i < passenger.first[i]; i++)
      {   
         first1[i] = passenger.first[i];
      }
      
      if(strcmp(last0, last1) == 0)
        {
         return (strcmp(first0, first1) < 0);
        }
      return (strcmp(last0, last1) < 0);
   }