COSC 1315 Fundamentals of Programming

COSC 1315 - Fundamentals of Programming
Allan Kochis

Relational operators are used to describe the relationship between operands. The relational operators are :
1. > greater than
2. >= greater than or equal.
3. < less than
4. <= less than or equal
5. == equal ( do not confuse this with =).
6. != not equal
  
  If the relationship is true the expression returns a 1. If it is false the expression returns a 0.

Logical operators are used to build complex expression. The 3 logical operators are :

&& and
If either operand is zero, and returns a 0. If both operands are non zero and returns a 1.

A B A && B
True True True
True False False
False True False
False False False
|| or
If both operands are zero return a zero (0), If either operand is non zero return a 1.

A B A || B
True True True
True False True
False True True
False False False
! not
Returns 0 if given non zero, returns 1 if given 0.

A ! A
True False
False True

A	B	A && B
True	True	True
True	False	False
False	True	False
False	False	False

A	B	A \|\| B
True	True	True
True	False	True
False	True	True
False	False	False

A	! A
True	False
False	True

Precedence
The order of precedence is ! && ||
Fill in the following Truth table

A	B	C
True	True	True
True	True	False
True	False	True
True	False	False
False	True	True
False	True	False
False	False	True
False	False	False

A	B	! (A && B)
True	True
True	False
False	True
False	False

Logical Constructs

Logic

Code

	if(iMonth == 1 )
	{
		strMonth="January";
	}

if else

Logic

Code

	if(temp < 60)
	{
		strText="Turn up the heat!";
	} else {
		strText="I am ok";
	}

if else if else

Logic

Code

	if(Temp < 60)
	{
		strText="Turn up the heat";
	} else if (Temp > 90)
		{
			strText="Turn on the AC";
		} else {
			strText="I am ok";
		}

Cascading

Logic

Code 1.

	if (day ==0) strName="Sunday";
	else if (day==1) strName="Monday";
             else if (day==2) strName="Tuesday";
                  else if (day==3) strName="Wednesday";
                       else if (day==4) strName="Thursday";
                            else if (day==5) strName="Friday";
                                 else if (day==6) strName="Saturday";

Code 2.

	switch (day) {
		case 0 : strName="Sunday";
			 break;
		case 1 : strName="Monday";
			 break;
		case 2 : strName="Tuurday";
			 break;
		case 3 : strName="Wednesday";
			 break;
		case 4 : strName="Thursday":
			 break;
		case 5 : strName="Friday";
			 break;
		case 6 : strName="Saturday":
			 break;
        } // end of switch