Data Structures Tutorial

Data Structures Tutorial Asymptotic Notation Structure and Union Array Data Structure Linked list Data Structure Type of Linked list Advantages and Disadvantages of linked list Queue Data Structure Implementation of Queue Stack Data Structure Implementation of Stack Sorting Insertion sort Quick sort Selection sort Heap sort Merge sort Bucket sort Count sort Radix sort Shell sort Tree Traversal of the binary tree Binary search tree Graph Spanning tree Linear Search Binary Search Hashing Collision Resolution Techniques

Misc Topic:

Priority Queue in Data Structure Deque in Data Structure Difference Between Linear And Non Linear Data Structures Queue Operations In Data Structure About Data Structures Data Structures Algorithms Types of Data Structures Big O Notations Introduction to Arrays Introduction to 1D-Arrays Operations on 1D-Arrays Introduction to 2D-Arrays Operations on 2D-Arrays Strings in Data Structures String Operations Application of 2D array Bubble Sort Insertion Sort Sorting Algorithms What is DFS Algorithm What Is Graph Data Structure What is the difference between Tree and Graph What is the difference between DFS and BFS Bucket Sort Dijkstra’s vs Bellman-Ford Algorithm Linear Queue Data Structure in C Stack Using Array Stack Using Linked List Recursion in Fibonacci Stack vs Array What is Skewed Binary Tree Primitive Data Structure in C Dynamic memory allocation of structure in C Application of Stack in Data Structures Binary Tree in Data Structures Heap Data Structure Recursion - Factorial and Fibonacci What is B tree what is B+ tree Huffman tree in Data Structures Insertion Sort vs Bubble Sort Adding one to the number represented an array of digits Bitwise Operators and their Important Tricks Blowfish algorithm Bubble Sort vs Selection Sort Hashing and its Applications Heap Sort vs Merge Sort Insertion Sort vs Selection Sort Merge Conflicts and ways to handle them Difference between Stack and Queue AVL tree in data structure c++ Bubble sort algorithm using Javascript Buffer overflow attack with examples Find out the area between two concentric circles Lowest common ancestor in a binary search tree Number of visible boxes putting one inside another Program to calculate the area of the circumcircle of an equilateral triangle Red-black Tree in Data Structures Strictly binary tree in Data Structures 2-3 Trees and Basic Operations on them Asynchronous advantage actor-critic (A3C) Algorithm Bubble Sort vs Heap Sort Digital Search Tree in Data Structures Minimum Spanning Tree Permutation Sort or Bogo Sort Quick Sort vs Merge Sort

Array Data Structure

Data Structure Array: The array is a non-primitive and linear data structure that is a group of similar data items. That is, it can store only one type of data. The array is used to store a group of data objects. The array is a static data structure that means we can allocate memory only in compile-time and cannot convert it to run-time.

Array Memory representation

The following figure represents an int type array in which is eight elements. The index of the array starts at 0 and ends at 7 due to 8 elements.

Array Data Structure

Need of the Array

An array is especially helpful when working with lots of variables of the same data-type. 

For example, let's take a record of 100 employees, and now that record needs to be stored in the system. To solve this problem, either you have to create the 100 variables of int data-type or create an array of int type.

Program without array:

#include <stdio.h>
#include   <conio.h>
void main ()
{
int emp1_salary = 1500, 
emp2_salary = 500, 
emp3_salary = 500, 
emp4_salary = 1500, 
emp5_salary = 3500, 
emp6_salary = 2500, 
emp7_salary = 1500, 
emp8_salary = 4500, 
emp9_salary = 1500, 
emp10_salary = 500, 
emp11_salary = 2500, 
emp12_salary = 3500, 
emp13_salary = 4500, 
emp14_salary = 4000, 
emp15_salary =4500;
float avg = (emp1_salary + emp2_salary + emp3_salary + emp4_salary + emp5_salary +   emp6_salary + emp7_salary + emp8_salary + emp9_salary +   emp10_salary + emp11_salary + emp12_salary +   emp13_salary + emp14_salary + emp15_salary) / 15;
printf(avg);
}  

Program by using array:

#include <stdio.h>
#include   <conio.h>
void main ()
{    int emp_salary [15] = {1500,        500, 500, 1500, 3500, 4500, 1500, 500, 1500, 3500, 4500, 2500, 3500,        4000, 4500);   
int i;    float avg;   for (i=0; i<15; i++)    
{   avg = avg + emp_salary[i];}printf(avg);}     

See both programs; the first program is complex than the second program because the line of code of the first program is more than the second program. Therefore, Array is the best option when working with lots of variables of the same data-type.

Types of Array

There are three types of Array, as shown in the following:

  1. One dimensional Array
  2. Two-dimensional Array
  3. Multi-dimensional Array

One dimensional Array

One-dimensional arrays are those arrays that contain only one subscript. It is used to store data in the linear form.

One-dimensional Array declaration: 

data_type array_name[size];

For example:

int teacher[20];
float percentage[20];
char name[50]; 

Initializing One-Dimensional Array:

The array elements can be initialized after the array is declared. The initializer of the array is defined within braces and separated by commas.                        

int age[5] = {26,20,14,43,21};

Program of one-dimensional Array

 #include<stdio.h>
#include<conio.h>
int main()
{
int array[4], i;
for(i = 0; i < 4; i++)
{
printf("Enter a[%d] value: ", i);scanf("%d", &array[i]);
}
printf("\nPrinting elements of   the array: \n\n");for(i = 0; i < 4; i++){printf("%d ", array[i]);}return 0;
} 

Output

Enter a[0] value: 10
Enter a[1] value: 20   
Enter a[2] value: 30   
Enter a[3] value: 40       
Printing elements of the array:       10 20 30 40       

Two-dimensional Array

Two-dimensional arrays are those arrays that contain two subscripts. A two-dimensional array is also known as the matrix. The first subscript of the Array is denoted the number of rows in the array, and the second subscript is denoted the number of columns in the array. The total number of elements in a two-dimensional array is ROW*COLOUMN

One-dimensional Array declaration: 

data_type array_name[row_size][coloum_size];

For example:

int teacher[20][30];

Initializing a Two-Dimensional Array:

int teacher[2][3] = {1, 2, 3, 7, 8, 6 };
#include<stdio.h>
#define ROW 2
#define COL 3
int main()
{       
int matrix1[ROW][COL], matrix2[ROW][COL], matrix3[ROW][COL];      
int i, j;             printf("Enter first matrix:   \n\n");             
for(i = 0; i < ROW; i++)          
{                 
for(j = 0; j < COL; j++)              
 {                  
printf("Enter a[%d][%d]: ", i, j);                  
scanf("%d", &matrix1[i][j]);              
  }
              }
              printf("\nEnter Second matrix:   \n\n");  
           for(i = 0; i < ROW; i++)            
  {                 
  for(j = 0; j < COL; j++)     
              {                     
   printf("Enter a[%d][%d]: ", i, j);              
          scanf("%d", &matrix2[i][j]);               
      }           
      }     
    for(i = 0; i < ROW; i++)         
 {           
       for(j = 0; j < COL; j++)           
          {                     
 matrix3[i][j] = matrix1[i][j] + matrix2[i][j] ;                 
     }           
 }          
  printf("\nsum of array: \n\n");        
        for(i = 0; i < ROW; i++)               
   {             
       for(j = 0; j < COL; j++)           
             {           
 printf("%5d ", matrix3[i][j]);                       
  }           
  printf("\n");       
     }
return 0;}                                                                                                                                      

Output

Enter first matrix:       
Enter a[0][0]: 22   
Enter a[0][1]: 13   
Enter a[0][2]: 43   
Enter a[1][0]: 38   
Enter a[1][1]: 94   
Enter a[1][2]: 15       
Enter Second matrix:       
Enter a[0][0]: 17   
Enter a[0][1]: 26   
Enter a[0][2]: 78   
Enter a[1][0]: 44   
Enter a[1][1]: 24   
Enter a[1][2]: 80       
sum of array:       matrix1 + matrix2 =       39 39 121   82 118 95    

Multi-dimensional Array (3-d)

Multi-dimensional arrays are those arrays that contain more than two subscripts. The multi-dimensional array is also known as the 3-d array.

Advantages of Array

The advantages of the array are the following:

  1. It can be easily implemented.
  2. Different data items of the same type can be displayed by just one name.
  3. It can store multiple data items at the same time.

Disadvantages of Array

The disadvantages of the array are the following:

  1. The array is a static data structure due to which its size is already defined. 
  2. We have to traverse the entire array to delete and insert an element in the array.



ADVERTISEMENT
ADVERTISEMENT