Basic C++ Flashcards
selection structure (definition)
statement that allows the program to choose between alternative actions (make a decision)
selection structure (examples)
- ifj
if statement building blocks are…
- logical expressions
action
a C++ statement
C++ statements that can be actions
- output (cout)
bool data type
- used to store a logical value
bool example code
bool valid, finished;
logical (Boolean) expression (definition)
an expression that evaluates to true or false
relational operators
operators that are used to compare values
logical (Boolean) expression (facts)
- in C++, any non-zero value is considered true, 0 is considered false
relational operators (definition)
operators that are used to compare values
relational operators (examples)
< <= > >=
Equality operator (symbol)
==
Assignment operator (symbol)
=
Equality operator (==) vs. Assignment operator (=)
The equality operator (==) is used to compare values the assignment operator (=) is used to store values. It is important to use the == operator in logical expressions.
Compare like types (tip)
When creating logical expressions is to best to
logical operators (definition)
operators used to connect or change logical expressions
logical operators (examples)
! - not
Operator precedence
!
short circuit evaluation
process in which the computer evaluates a logical expression from left to right and stops as soon as the value of the expression is known.
basic if statement syntax
if (logical expression)
if statement semantics
evaluate logical expression
extended form of if statement syntax
if (logical expression)
extended form of if statement semantics
evaluate logical expression
Nested if statements
if the logic needed requires more than two alternatives, __________ can be used.
repetition structure
statement that allows an action to be repeated (iteration, looping)
C++ repetition statements (examples)
while
while statement syntax
while (logical expression)
while statement semantics
step 1: evaluate expression
infinite loop definition
if the expression remains true, the loop will not be exited
++ increment operator (e.g., num++;)
unary operator used to add 1 to a variable
– decrement operator (e.g., num–;)
unary operator used to subtract 1 from a variable
batch processing
all input gathered together and placed in a file, program designed to get data from file as needed (no prompting required)
Linux input redirection operator: <
changes the default input source to a specified file
Linux input redirection operator: >
changes the default output destination to a specified file
Linux redirection sample code
[bobby ~]$ ./a.out < myinput > myoutput
The key to designing a program to run in batch mode.
Design the program as if were interactive but leave out the prompts.
Count-controlled looping
Loop designed to run a specific
Sentinel-controlled loop
Loop designed to repeat an action until a special value is encountered.
Sentinel-controlled syntax
while (data != sentinel)
End-of-file controlled loop
Loop designed to continue processing data until all data in the file has been read.
End-of-file controlled loop syntax
!cin.eof()
Flag-controlled loop
Loop where bool variable is used to control
Flag-controlled loop syntax
bool finished = false; //finished is the flag
for statement
a statement specifically designed for implementing count-controlled loops.
for statement syntax
for (initial statement; loop condition; update statement)
for statement semantics
step 1: execute initial statement
Nested looping
When the solution to a task requires repetition, and the task must be repeated, ________ can be used.
The two types of functions in C++
- value-returning function, and
value-returning function (definition)
Function designed to compute and return EXACTLY ONE value using a return statement.
void function
Function that is series of statements designed to perform a task. This type of function does not have a specific data type.
What is needed to implement a function
consists of a heading and a body, placed after the main function
function prototype
placed after using statement and const declarations, before heading for main function - provides information to compiler about the function
function call
placed inside any function, used when you want the statements in the function to be executed.
function syntax
// preprocessor directives
value-returning function definition syntax
data_type function_name (formal parameter list) // heading
formal parameter (definition)
variable declared in a function heading
formal parameter (syntax)
(data_type identifier, data_type identifier, …)
parameters passed by value
a copy of the actual parameter’s value is sent to the function. The function uses the copy in all
local variable
A variable declared inside a program block is said to be local to the block. It exists and is recognized only inside the program block.
actual parameter
a variable or expression listed in a call to a function.
void function
a series of statements designed to perform a task. This type of function does not have a specific data type and does not directly return a value.
void function syntax
void function_name (formal parameter list) //heading
parameters passed by reference
the address (memory location) of the actual parameter is sent to the function. The function accesses the actual parameter in all statements that reference the parameter. Any changes made to the parameter are made to the actual parameter. The original parameter (in the calling function) is changed.
True or False: A void function call is a stand-alone statement.
True
Scope of an identifier
the region (part) of a program where an identifier is recognized (visible) and accessible.
Local identifier
identifier declared within a function (or block)
Global identifier
identifier declared outside of every function definition
automatic variable
the memory for a local variable is (by default) allocated at declaration and deallocated at block exit
static variable
the memory for a global variable is allocated at declaration and de-allocated when program is finished executing
syntax for making local variables static
static datatype variablename = startvalue;
pwd
lists the current working path directory
make
alternative method for compiling your C++ programs where each of your executable files will have different names so that if you want to run several different programs in the same directory, you do not have to recompile each time you want to run a different program.
when a parameter is passed by reference, the actual parameter MUST be a _______
variable
computer
an electronic device capable of performing commands (input, output, storage, arithmetic and logic operations)
hardware
the physical components of a computer and its surrounding (peripheral) devices
software
sets of instructions to be executed by the computer, i.e., programs
system software
programs designed to control the computer
operating system
a set of programs that control overall computer activity and provide services
Windows and Linux
The two operating systems that the CS computer lab machines boot to.
CPU and main memory, secondary storage, input and output devices
basic components of computer hardware
application software
programs designed to perform specific tasks
system software and application software
the two main types of software
editor
program used to create and modify text based files
emacs
editor used in CS labs
case sensitive
both linux and C++ are ___________, meaning that upper case and lower case letters are different
ASCII
collating code commonly used by computers for encoding data into sequences of bits
128 (numbered 0-127)
the number of characters in ASCII
machine language, assembly language, and high-level language
types of programming languages
machine language
instructions made up of sequences of 0s and 1s
assembly language
instructions made up of mnemonic codes
high-level language
instructions are closer to natural language, use familiar words and symbols
machine language
programming language that:
assembly language
programming language that:
high-level language
programming language that:
BASIC, FORTRAN, Pascal, Java, C, C++
Examples of high-level languages
compiler
a program that translates instructions written in a high-level language into the equivalent machine code
g++
the compiler used in the CS labs for C++
}
the parts required in every C++ program
Program Development
a problem solving process
Analysis, Implementation, Maintenance
Three steps of Program Development
algorithm
a step-by-step procedure for solving a problem in a finite amount of time
source file
a human readable file that contains C++ program
object file
executable version of program
program
a sequence of statements whose objective is to accomplish a task
programming
process of planning and creating a program
programming language
a set of rules, symbols, and special words
syntax
grammar rules of the language; compiler will try to identify and locate syntax errors
semantics
meaning of the instructions in the language; compiler cannot find these errors - often called logic errors
comments
nonexecutable statements that are included in a program to provide information about what the program does, how it works, what input is expected, what output is generated, who wrote it, etc.
preprocessor directives
tells the computer where to find the library for operations and data types
