Tutorial Week 4 (02/01/12)

--what does #include do?
     --to access the files included, like the codes inside them.
     --copy and paste files included into ur files

--difference b/t <...> and "..."
     --<...> extended libraries, can be found in linux.
     --"..." look through the current directory.

--why to include headers?
     --similar to "provide" in scheme.

--Assignment 3
     --g++ -c my-func.cpp
          --.c allows you to compile
          --.o not ready to be compile yet
     --g++ main.cpp my-func.o -o solution
     --

     --multiple functions with the same names?
               --

     --#include <cassert> (in c++)----in c, "assert.h"
       #include <cstdlib> (in c++)  ----in c, "stdlib.h"

        why to use assert? --

     --input -- cin
               -- cout << i << "Hello";  ok to do that;
               --cin >> i >> n;  <=> cin >> i; cin >> n;
               --each cin will not include whitespace, but will at a whitespace;


     --strings
             --in c++, a string is an object;
                in c, A character array terminated with a null character '\0';
             --std::string?
                         --int a;
                           int main () {
                              int a;
                              ::a = 7;     //:: assign 7 to the global a;
                              }

                         --int a;
                           int main () {
                              struct b {
                                   ...
                                   int a; };
                              b::a=7;     //assign 7 to the a inside b;
                              }

--use :: operator in header files;
--use 'using namespace std' only in main.cpp files, not headers
--in general, use std:: when not using namespace;

--command line arguments:
     --int main (int argv, char* argc[])
          --argv: number of arguments, including command name
          --argc: array of pointers to character strings(C strings)

--How to create the previous program
--instead of using cin for input, use command line arguments
          string s; // s = hi
          s = argc[0];
          string s(argc[0])