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ZYBOOKS NOTES
https://www.icloud.com/pages/0qcM__l6ZT3igEg1pWhlXdmsQ#ZYBOOKS_NOTES
Section One (1.1-1.6)
1.1 Programming
- A program is instructions executing one at a time.
- Basic instructor types:
- Input: A program gets data
- Process: Performs computations in the data
- Output: Puts the data somewhere
- Uses variables to refer to data (x, y, z)
- Computational thinking - creating a sequence of instructions to solve a problem
- Sequence of instructions to solve a problem is an algorithms.
1.2 Programming Basics
- Code: The textual representation of a program
- Starts with main ( ) {
- Each statement ends with ;
- Int___ introduces an integer
- Cout prints to screen
- Return 0; ends the program
- Cin is characters in
- cout<<“__” prints text
- cout<<____; outputs a variable’s value
1.3 Comments and White Space
- Comment: text that a programmer adds to a code, not read by an computer
- Single line comment: starts with // and includes all the following text on that line.
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- Multiline comment: starts with /* and ends with */ where alll the text between is the
comment.
- Whitespace: Blank spaces between items within a statement and blank lines
between statements
1.4 Error and Warnings
-Syntax Errors: Violates a programming language’s rules on how symbols can be
combined to create a program
-Logic Error or Bug: Code works but completes incorrect functions.
1.5 Variables
- Variable Declaration: A statement that declares a new variable, specifying name and
type.
- Assignment Statement: Assigns the variable on the left hand side of the = to the right
hand side.
1.6 Variables and Assignments
Assignment: Assigns a variable with a value such as x = 5
Section Two (2.1-2.9)
2.1 Arithmetic Expressions
- Expression: A combination of items like variables and such
- Literal: A speci c value in code
- Operator: A symbol that performs a function in calculation
2.2 Arithmetic Conventions
- Put a space around operators
- Compound Operators: numBox + = 2 is equivalent to numBox + 2
- Integral Literals cannot have commas
2.3 Floating Point Numbers
- Floating point numbers: a real number containing a decimal point that can appear
anywhere in the number
- A double variable: stores a oating-point number
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- Floating-point literal: A number with a fractional part
- Using int for countable items and double for measurements
2.4 Characters
- Identi er: A name created by a programmer for an item
- Sequence of letters from a - z
- Start with a letter or underscore
- They are case sensitive
2.5 Characters
- Declare a character variable: char ___;
- Character literal can store one variable
- Ex: myKey = ‘m’;
- Cin can be used to get a one character output
- Ex: cin>>myKey ==> m
- Escape sequences:
- \n ==> new line
- \+ ==> new tab
- \’ ==> single quote
- \“ ==> double quote
- \\ ==> backslash
2.6 Strings
- String: sequence of characters
- String Literal: Surrounds a character sequence with double quotes
- Whitespace Character: a character used to represent horizontal and vertical spaces
in text
- userString puts variables in until whitespace
- Ex: cin>>userString;
- Hello there (will put in only Hello)
2.7 Constant Variables
-Useless Information
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2.8 Type Conversions
-Type Conversion: A conversion of one data to another
-Type Cast: Explicitly converts a value of one type to another type
2.9 Integer Division and Modulo
- Modulo Operator (%) evaluates the remainder of the division
- Ex: 23%10 —> 3
- Both sides of the % must be integers
Section Three (3.1-3.5)
3.1 Using Math Functions
- Function: A list of statements executed by invoking the function's name, such
invoking known as a function call.
- Arguments: Function input values that appear within ( ).
- Functions:
- sqrt(x)- square root of a function
- pow(x,y)- raise x to y power
- fabs(x)- absolute value of x
3.2 User-de ned function Basics
- Functions are prede ned statements for repeatably used functions, and help speed
up programs and reduce redundancy.
- Functions are named lists of statements:
- Function De nition: The new function's name and a block of statements
-Function Call: An invocation of a function name causes the function to execute
-Parameter: A function input speci ed in a function de nition
-Argument- A value provided to a function's parameter during a function call
3.3 Return
-Return Statement: A statement a function returns
-void statement: Indicates the function does not return any value
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3.4 Reasons for De ning Functions
- Allows for easier reading for the program by people
-Programmers commonly use functions to write programs modularly and incrementally
- Modular Development: The process of dividing a program into separate
modules that can be developed and tested separately and then integrated into a single
program.
-Incremental Development: A process in which a programmer writes, compiles,
and tests a small amount of code, then writes, compiles, and tests a small amount
more.
-Function Stub: A function de nition whose statements have not yet been
written.
3.5 Common Errors
-Nothing of importance
Section Four (4.1 - 4.3)
4.1 Unit Testing
- Unit testing: The process of individually testing a small part of a program, usually a
function
- Testbench: Program that checks that a function returns the correct output values
through inputing values known as test vectors
- Assert() is a function that returns an error message and exits the program if assert ()'s
input expression is false
-Boarder cases: Inputs that represent the extreme of input values into a function.
4.2 Scope of Variable/Function De nitions
-Scope: The de ned variable or function item that is visible to a certain amount of code
-Global Variable: A variable declared outside any function
-Local Variable: A variable declared inside a function
-Function Declaration: Speci es the function's return type, name, and parameters, also
known as a function prototype
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4.3 Debugging
-Debugging: The process of determining and xing the cause of a problem in a
computer program also known as troubleshooting.
Section Six (6.1-6.5)
6.1 Loops
-Loops: A program construct that repeatedly executes the loop's statements (known as
the body) while the loop's expression is true. When false, execution proceeds past the
loop.
6.2 While Loops
-While Loop: A program that repeatedly executes a list of sub-statements (known as a
loops body) while the loop's expression evaluates to true. Each execution is an
iteration.
6.3 More While Examples
-sentinel value: special value indicating the end of a list
6.4 Function with Branches/Loops
-nothing
6.5 Developing Programs Increment
Section Seven (7.1-7.5)
7.1 For Loops
-For Loop: A loop that loops a speci c number of time and has three parts: a loops
variable initialization, a loops expression, and a loop variable update.
- for (i = 0; i < 10; ++1)
7.2 More For Loop Examples
- The loops are initialized to i = 0
- The ++ operators: pre x form (++i) and post x form (i++)
7.3 Nested Loops
- Nested Loop: Loop that appears in the body of another loop. Parts referred to as the
inner and outer loops.
7.4 Variable Name Scope
-Scope: The region of code where a declared name is valid
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Section Eight (8.1-8.2)
8.1 String Access Operations
-A string is a sequence of characters in memory. Each string character has a position
number called an index that starts from zero.
- at(): variable.at(x) gets the x index of a string.
- can use at() to replace a string index in a word.
variable.at(3) = "!";
runs --> run!
-.size() returns the length of a string
x = word
x.size() --> 4
-.append adds letters to a word
x = word
x.append("!!!") --> word!!!
- index = length - 1
8.2 Loops and Strings
-Nothing
