-----BASIC C++ PROGRAM TEMPLATE-----

#include <iostream> 
using namespace std; 
 
int 
main (int argc, char **argv)
{ 
  /* Variable Declaration */ 
 
 
  /* Instructions */ 
 
  return 0; 
} 
------ COMMENTS ---------------

/* 
   Put explanatory messages for yourself and other
   programmers (not the computer) in comments
   like this one 
*/

//single line comments look like this

------EDIT SAVE COMPILE RUN -------------


or EDIT, SAVE, COMPILE, FIX COMPILER ERRORS, RUN, CHECK OUTPUT

1) Edit your code with an editor like emacs or nano (learning to navigate in at least
one editor on polaris is going to be important for this class)

E.g.   emacs -nw my program.cpp
       OR
       nano myprogram.cpp

Remember to save you changes!


2) Compile your code with a compiler (translates
human readable source code into executable format
the computer needs to actually run the program)
E.g. g++ myprogram.cpp

Fix any compiler errors! 
Go to first problem by it's line number and fix.

3) Run your program 

E.g. ./a.out

Check that the output of the program is what you expect


-----SIMPLE TYPES-----

TYPE	    EXAMPLES
int	    0,1, -1, 2, -2,...
	
unsigned int  0, 1, 2,3, 4, ...

float	    2.89, 67777799.0, -1000000000.0
double

char	    'a', 'Z', '\n'

bool	    true, false


string	    "August", "This sentence is a string"


possible numeric values are not infinite like in math
- e.g. there is a fixed amount of space to store an int
and so unlike in real like there is a maximum integer

unsigned int vs int - use space to store all positives
    vs half positive and half negative


unsigned and int vs float
     float can store bigger and smaller numbers
     but to do so can give up precision


float vs double - more space used for both bigger numbers
and more precise numbers


-----SAMPLE VARIABLE DECLARATIONS------

int month;
char answer;
bool isReady = false;
char initial = 'A';
float wage = 8.50;
string name = "John Smith";
unsigned int year = 1996;

Remember to use descriptive variable names!!


-----INPUT/OUTPUT----

cin >> variable;


cout << "Hi\n";
cout << "Hi " << name << "\n";
cout << "Hi " << name << endl;


----- ARITHMETIC OPERATORS-------

+    add
*    multiple
-    subtract
/    divide (remember for ints gives just whole 
	    number part of answer, cuts off any decimal portion)
%    modulus (gives integer remainder after division)

remember order of operations like in math
can use parentheses to force/clarify the order you want

----- ASSIGNMENT STATEMENTS-------

Example assignment statements

hoursPerMonth = daysPerMonth*24;

age = age+1;

index = index -1;

total_price = num_item1 * item1_price + num_item2 *item2_price;

------- BOOLEAN EXPRESSIONS --------

boolean expressions evaluate to true or false

Example boolean expressions

bool isTransferStudent;
(isTransferStudent)

(month > 2)

(answer == 'Y')

------ COMPARE OPERATORS  -----------

==  equal
    (Remember one = sets something equal. Two == tests if 
     two things are equal)
    (Also remember that it is dangerous to test doubles with ==
    they may be very very close but not identical in precision)
!=  not equal
>   greater than
>=  greater than or equal
<   less than
<=  less than or equal


------ BOOLEAN OPERATORS ----------

&&     AND
||     OR

Combine boolean expressions to make a larger boolean expression

((month >=1) && (month <= 12))
((answer == 'Y') || (answer == 'y'))


------ IF-ELSE STATEMENTS ---------------

if (boolean expression)
{
	true_statement1;
	true_statement2;
	
} else {
       false_statement1;
       false_statment2;
}

Notes: Always using {} in your if statments is safer

else clause is optional

------ IF-ELSE IF-ELSE STATEMENTS ---------------
unsigned y;

if (y==1)
{
	1	
} else if (y< 10)
{
	0, 2-9

} else if (y < 20){

       10-19
} else {

       20+
}

Can have as many else if clauses as you like

Evaluated one at a time and take first option
that matches!  Don't take multiple branches
even if match multiple
 

Always have exactly 1 if, can have 0-N else if,
can have 0 or 1 elses