Array List and its Operations
Array
- Same type of elements at contiguous location
- Same name and type
To refer to an element, specify
- Array name and position number
Name of array (Note that all elements of this array have the same name, c)
Format: arrayname[ position number ]
- First element at position 0
- n element array c:
c[ 0 ], c[ 1 ]…c[ n – 1 ]
Array elements are like normal variables
c[ 0 ] = 3;
cout << c[ 0 ];
Performing operations in subscript. If x = 3,
c[ 5 – 2 ]
or c[ 3 ]
Or c[ x ]
Size of an Array
- Total size of an array in bytes?
- Total bytes = number of bytes in type x number of elements
- e.g. int sample[10];
Declaring Arrays
Declaring arrays – specify:
- Name
- Type of array
- Number of elements
int c[ 10 ];
float hi[ 3284 ];
Declaring multiple arrays of same type
- Similar format as other variables
int b[ 100 ], x[ 27 ];
What Operations Can You Perform on an Array?
- Traversal
- Insertion
- Deletion
- Searching
- Sorting
Types of Arrays.
types of arrays
One-Dimensional Arrays
You can imagine a 1d array as a row, where elements are stored one after another.
Multi-Dimensional Arrays
Two-Dimensional Arrays
Getting Values
int MyArray[5];
cin>>MyArray[0];
cin>>MyArray[1] ;
cin>>MyArray[2] ;
cin>>MyArray[3] ;
cin>>MyArray[4] ;
- Or
for(int i = 0; i < 5; i++)
cin>>MyArray[i];
Examples Using Arrays
Initializers
int n[ 5 ] = { 1, 2, 3, 4, 5 };
- If not enough initializers, rightmost elements become 0
- If too many initializers, a syntax error is generated
- int n[ 5 ] = { 0 }; Sets all the elements to 0
If size omitted, the initializers determine it
int n[] = { 1, 2, 3, 4, 5 };
- 5 initializers, therefore n is a 5 element array
Arrays
int a[10], b[10];
// …
a = b; // error – illegal
for(int i = 0; i < 10; i++)
a[i] = b[i]; //legal
Write a program to input an array of size 10 from the user and
- Find and print the minimum value in array
- Find and print the maximum value in array
Finding Minimum and Maximum
int main()
{
int i, min_value, max_value, list[10];
for(i=0; i<10; i++)
cin>>list[i];
// find minimum value
min_value = list[0];
for(i=0; i<10; i++)
if(min_value>list[i]) min_value = list[i];
cout << “\nminimum value: ” << min_value << ‘\n’;
// find maximum value
max_value = list[0];
for(i=0; i<10; i++)
if(max_value<list[i]) max_value = list[i];
cout << “maximum value: ” << max_value << ‘\n’;
return 0;
}
