CC 203 Midterms Review: Arrays and Strings

Simple Data Type

variables of this type can store only one value at a time

Structured Data Type

a data type in which each data item is a collection of other data items

Array

a collection of a fixed number of components

One Dimensional Arrays

components are arranged in list form

Syntax for declaring one dimensional arrays

dataType arrayName [intExp];

intExp

any constant expression that evaluates into a positive integer

General Syntax for accessing array elements

arrayName[indexExp]

indexExp

called the index (an integer with a nonnegative integer value)

Basic Operations of a one-dimensional array

Initializing, Inputting Data, Outputting data stored in an array, Finishing the largest and or smallest element

Index of an array

is in bounds if the index is >= 0 and <= ARRAY_SIZE -1

Out of bounds index

the index is out of bounds if it does not meet the criteria of being in bounds

Array Initialization during Declaration

Arrays can be initialized during declaration with values placed between curly braces

Partial Initialization of Arrays during Declaration

Size determined by the number of initial values in braces

Aggregate Operation

any operation that manipulates the entire array as a single unit, not allowed on arrays in C++

Arrays as Parameters to Functions

Arrays are passed by reference only

Constant Arrays as Formal Parameters

They can prevent a function from changing the actual parameter when passed by reference

Base Address of an Array

address (memory location) of the first array component

Functions cannot return a value of the type Array

C++ does not allow functions to return a value of type array

Integral Data Types and Array Indices

C++ allows any integral type to be used as an array index

Sequential Search

Searching a list for a given item, starting from the first array element

Selection Sort

rearrange the list by selecting an element and moving it to its proper position

Character Array

an array whose components are of type char

C-Strings

null-terminated ('\0') character arrays

Example of C-Strings

'A' is the character A; "A" is the c-string A; "A" represents two characters: 'A' and '\0'

Maximum string length in C-Strings

the largest string it can store is 15 characters if it has 16 components

Omitting size of an array during initialization

Size of an array can be omitted if the array is initialized during declaration

strcpy

Function used to copy a string.

strcmp

Function used to compare two strings.

strlen

Function used to determine the length of a string.

C-Strings

Character arrays that are null-terminated.

ASCII character set comparison

Character strings are compared using the ASCII values, e.g., 'Air' < 'Boat'.

cin >> name

Reads the next input c-string into the variable name.

cin.get(str, m+1)

Reads the next m characters into str, excluding the newline character.

cout << name

Outputs the content of name to the screen.

Null character

Character that indicates the end of a c-string.

c_str function

Converts a string variable to a c-string.

Parallel arrays

Two or more arrays that hold related information.

Two-dimensional arrays

Collections of components arranged in rows and columns.

Declaration syntax for two-dimensional arrays

dataType arrayName [intExp1][intExp2].

Accessing components in a two-dimensional array

arrayName[indexExp1][indexExp2] where indexExp1 and indexExp2 specify row and column.

Sales[5][3]

Example of accessing a component in a two-dimensional array.

Two-dimensional array initialization

Can be initialized at declaration with elements enclosed in braces.

Unspecified elements in number arrays

Are set to 0 when not explicitly initialized.

Two-dimensional array

A structured data type with a fixed number of components of the same type, arranged in a table form.

Row processing

Processing a two-dimensional array one row at a time.

Column processing

Processing a two-dimensional array one column at a time.

One-dimensional array

An array where elements are arranged in the form of a list.

Base address

The address of the first array component.

Passing two-dimensional arrays

Two-dimensional arrays are passed by reference as parameters to a function.

Row order storage

Two-dimensional arrays are stored in row order.

Array of strings

A collection of strings that can be manipulated using either the string data type or character arrays (c-strings).

Declaration of array of strings

To declare an array of 100 components of type string: string line[100].

N-dimensional array

A collection of a fixed number of elements arranged in n dimensions (n >= 2).

Declaration syntax for multidimensional arrays

dataType arrayName[intExp1][intExp2]... [intExp];

Accessing a component

To access a component: arrayName[index1][index2]...[indexEspn].

Array index

An expression that evaluates to a nonnegative integer, must always be less than the size of the array.

Function return for arrays

A function cannot return an array type value.

C-strings

C-strings are null terminated and are stored in character arrays.

Common c-string functions

Commonly used c-string manipulation functions include: strcpy, strcmp, strlen.

Parallel arrays

Arrays used to hold related information.

Accessing elements in two-dimensional arrays

To access an element, you need a pair of indices: one for row position, one for column position.

Sum by row

Calculating the total of each row in a two-dimensional array.

Sum of column

Calculating the total of each column in a two-dimensional array.

Largest element in each row and column

Finding the largest element for every row and every column in a two-dimensional array.