Programming In C++ Chapter 2

Front 1

Writing a program involves...

Back 1

designing a strategy for solving a problem and then using a programming language to implement that strategy.

Front 2

Every C++ function begins its execution from...

Back 2

the main function.

Front 3

Basic starting point when writing a program (header and footer):

Back 3

#include "stdafx.h"
#include <iostream>
#include <string>

using namespace std;

int main ( )
{

return 0
}

Front 4

Variables are...

Back 4

used to represent values that may be changed in the program.

Front 5

Declaring a variable...

Back 5

tells the compiler what type of data a variable can hold.

Front 6

Identifiers are...

Back 6

the names that identify elements such as variables and functions in a program.

Front 7

3 rules of identifiers:

Back 7

1 - must contain only letters, digits, and underscores.
2 - must start with a letter or underscore - never a digit.
3 - cannot be a reserved word

Front 8

Syntax for reading an input from the console:

Back 8

cin >>

Front 9

What is the assignment operator?

Back 9

=

Front 10

What is the term for a variable declared in a function that has not been assigned a value? What happens if this occurs?

Back 10

An uninitialized variable; its value is unpredictable.

Front 11

A constant...

Back 11

represents data that never changes.

Front 12

conventional syntax for identifiers:

Back 12

identifierSyntax

Front 13

conventional syntax and keyword for constants:

Back 13

CONSTANT; const

Front 14

integer data types

Back 14

int
short
long
byte

Front 15

Unsigned integers are...

Back 15

nonnegative integers

Front 16

floating-point number types:

Back 16

float
double

Front 17

The % operator is for ...

Back 17

integers only.

Front 18

The -- operator (w. keyword) increments a variable by 1. The -- operator (w. keyword) decrements a variable by 1.

Back 18

increment (++); decrement (--)

Front 19

The double data type indicates...

Back 19

that the values are double-precision decimal point values.

Front 20

4 fundamental data types:

Back 20

integers
floating point numbers
characters
Boolean types

Front 21

tracing a program:

Back 21

a method of reviewing how a program works.

Front 22

What is the difference between sending the value of a variable and the name of that variable to the console?

Back 22

The value is not enclosed in quotation marks, but the name of the value or variable is.

Front 23

A single statement can be used to read multiple input.
Ex : to input three variables :

double num1, num2, num3;
cin >> num1 >> num2 >> num3;

Back 23

.

Front 24

syntax for declaring a variable:

Back 24

datatype variableName;

Front 25

A variable can be declared and -- in one step.
Ex : int count = 1

Back 25

initialized

Front 26

An expression represents...

Back 26

a computation involving values, variables, and operators that evaluates to a value. Ex : int x = x - 1;

Front 27

syntax for assigning a value to multiple variables:

Back 27

i = j = k = l;

Front 28

A constant must be...

Back 28

declared and initialized in the same statement.

Front 29

5 mathematical operators:

Back 29

+ , - , / , x , %

Front 30

A variable should be declared as unsigned when...

Back 30

its value is always nonnegative.

Front 31

For most applications, the -- numeric type is suitable for a decimal point number.

Back 31

double

Front 32

The -- function can be used to find the size of a type or a variable.

Back 32

sizeof (can be used in conjunction with a type as in sizeof(int), or a variable as in sizeof(area))

Front 33

A literal is...

Back 33

a constant value that appears directly in a program.

Front 34

Floating-point literals can be written in scientific notation (in the form of a x 10^b) with this syntax:

Back 34

numberEpower, or numberepower

Front 35

When both operands of a division are integers, the result of the division is the -- and the -- part is --.

Back 35

quotient; fractional; truncated

Front 36

The % operator is known as...

Back 36

the modulo

Front 37

The modulo works only with -- and yields the --

Back 37

integer operands; remainder after division.

Front 38

An exponent operation can be performed using...

Back 38

the pow(a, b) function , found in the cmath library.

Front 39

Some C++ compilers require that either a or b in pow(a, b) be...

Back 39

a decimal value.

Front 40

The -- function can be invoked to return the current time.

Back 40

time(0), found in the ctime header file, which returns the current time in seconds elapsed since the UNIX epoch. This can be further developed using the modulo to return the current time.

Front 41

An augmented assignment operator...

Back 41

allows you to combine assignment and numerical (math) operators.

Ex : The following statements are equivalent. The second uses an addition assignment operator.

count = count + 8
count += 8

The same syntax applies to the remaining 4 numerical operators.

Front 42

The syntax for increment and decrement operators:

Back 42

int i = 3;
i++; // i becomes 4
i-- // i becomes 2

Front 43

Floating-point numbers can be converted into integers using...

Back 43

explicit casting

Front 44

When assigning a floating-point value to an integer, the fractional part --

Back 44

is truncated, not rounded.

Front 45

A casting value...

Back 45

allows you to convert a value from one type to another.

Front 46

The syntax for explicit casting of a variable:

Back 46

static_cast<type>(value) where value is a variable, a literal, or an expression and type is the type you wish to convert the value to.

Front 47

"Widening a type" :

Back 47

Casting a variable of a type with a small range to a variable of a type with a larger range.

Front 48

"Narrowing a type" :

Back 48

Casting a variable of a type with a large range to a variable of a type with a small range -- May cause loss of precision.

Front 49

Example of static_cast:

double purchaseAmount;
cin >> purchaseAmount;
double tax = purchaseAmount * 0.06;
cout << "Sales tax is" << static_cast<int>(tax *100) / 100.0;

if user entered 197.55 for purchaseAmount...
tax is evaluated at 11.853
tax * 100 is 1185.3
static_cast<int>(tax * 100) is 1185
static_cast<int> (tax * 100) / 100.0 is 11.85

Back 49

.

Front 50

7 good programming habits

Back 50

Analyze problem
develop algorithm (design)
write code for program (implement)
compile code
run program
test results
document the program

Front 51

IPO

Back 51

input, process and output; the essence of system analysis.

Front 52

5 common elementary programming errors:

Back 52

Undeclared or uninitialized variables
Integer overflow (when a variable is assigned a value too large for the data type specified)
Round-off errors (the diff. between the calculated approximation of a number and its exact mathematical value - calculations involving f-p #s are not stored with complete accuracy.)
Unintended integer division (division between integers needs to have one operand entered with a decimal point to reflect precise value)
Forgetting header files (ctime, cmath, iostream etc)

Front 53

Compiler errors

Back 53

are usually syntax errors or omissions

Front 54

character data type

Back 54

char, initialized as in: char firstLetter = 'A'
a character literal is enclosed in single quotation marks

Front 55

ASCII code table

Back 55

computers use unique numeric code to represent each character. each printable character is assigned a different integer code.

Front 56

the operator prints in the direction of -

Back 56

data flow

Front 57

example - formatting double and float to limit number of digits after decimal point

Back 57

<< static_cast<int>(tax * 100) / 100.0;

this will drop decimal amounts after two decimals that we want. change multiplier and divisor to change number of places required.

Front 58

when our program compiles correctly, it means that it is free of -

Back 58

syntax errors

Front 59

programs that do not run correctly contain -

Back 59

runtime errors (cause to terminate abnormally) or logic errors (to produce incorrect results). we discover them by testing the program.