INDENTATION
	Use the flexibility of whitespace to make program readable
	Indentation standards vary -- be consistent in lining up
	different code the right way; EMACS and other environments
	automatically will indent on TAB

	Algorithm ==> stepwise directions to get a task done
	In this course we will study many algorithms that
		accomplish useful tasks

	Programs require the ability to TEST conditions and 
	take different conditions.  This provides a powerful
	capability to implement algorithms that can handle
	different cases

if statement in C++ implements conditionality:
   Syntax:
	if ( condition ) statement ;

	OR
	
	if ( condition ) statement ;
		else
	    statement ;

	COMMON MISTAKES: 
		leaving out "(" ")" around the "condition"
		not putting the ";" at the end of statement
			(either following the true path or 
				false path)

   Semantics:
	The condition is evaluated and it can be either
	true or false.  statement following the condition
	is evaluated if the condition tests to true
	statement following the "else" (if any) is executed
	if the condition tests false

	Condition:
		Comparison operators: > < >= <= == !=
		You can construct conditional expressions or 
			BOOLEAN type: evalutes to true or false
		Examples include:
			a > b
			c != d
		and so on
		Compound conditional expressions use: logical operators
			NOT  : !  (negation)
				if C is true !C is false and vice versa
			AND  : && (conjunction)
				C && D is true if C is true and D is
					true; false otherwise
			OR   : ||  (disjunction)
				C || D is false if C is false and D is
					false; true otherwise
		Example of simple conditional statement


"return" statement 
		exits the function in which you place it:
		return expression ;
		OR
		return;
		"return" can also be useful with "if" stmt
		avoids long complicated, compound statement



MAKE SURE YOU USE "&&" and "||"
		"&" and "|" have a different meaning (bitwise)
		if (a > b && c > d)
		   cout << "This" ; 
		else
		   cout << "That" ;


See example7.cpp and example7a.cpp

"bool" type:
	values: true and false
	operators: logical operators !, &&, ||


Connection between "bool" and "int"
	value 0 : false
	non zero : true
        Use bool rather than int; it is better style
	in all cases because it is easier to follow


TRUTH TABLES
		C     D       !C      C && D       C || D
	      true   true    false     true          true
	      true   false   false     false         true
	      false  true    true      false         true
	      false  false   true      false         false


OPERATOR PRECEDENCE
		!   highest priority (this is also a UNARY
			OPERATOR -- applies to a single OPERAND)
		&& and ||  lower priority than !
		Examples of compound logical expressions and
			rules of precedence


Usefulness of NESTING if statements:
	if (condition1)
	   if (condition2)
	      statement1;
           else statement2;
	else statement3;


Nested If statement example

Dangling else problem:
	if (condition1)
	   if (condition2)
		statement1;
	   else statement2;
	Does statement2 associate with "condition2" being false
		or with "condition1" being false?
		Style hint: make the logic easier to understand
			by using { } as needed...

	// associate statement2 with condition1 being false
	if (condition1)
	   { 
	   if (condition2)
		statement1;
           }
	   else statement2;

	// associate statement2 with condition2 being false
	// this is the default!!
	if (condition1)
	   if (condition2)
		statement1;
	   else statement2;

	OR
	// if you want to be more careful:
	if (condition1)
	{
	   if (condition2)
		statement1;
	   else statement2;
	}


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