Page 59 - DCAP407_DATA_STRUCTURE

Data Structure

Algorithm for Linear search
Let A be a linear array with N elements and ITEM be the given item of information. The search
algorithm will find the location LOC of ITEM in A or sets LOC :=0 if the search fails. The algorithm is
as follows:
1. Start
2. [Insert ITEM at the end of A.] Set A[N+1] :=ITEM
3. [Initialize counter.] Set LOC :=1

4. [Search for ITEM.]
(a) Repeat while A[LOC] ≠ ITEM:
(b) Set LOC := LOC + 1
[End of loop]
5. [Successful?] If LOC = N + 1, then: Set LOC := 0
6. Exit
The following example illustrates the concept of searching an element in a linear array.

#include<stdio.h>
#include<conio.h>
#include<stdlib.h>

void main()
{
/* Declaring array M that can store 20 integers and the variables ele, i and num
as integer variables */

int M[20], i, ele, num;01
clrscr(); //Clears the previously entered data
printf("\nEnter the number of elements to insert in an array: ");

/*Accepts the number of elements from the user to store in the array M*/
scanf("%d", &num);

/*Accepts input from the user until i value is less than the num entered*/
for(i=0;i<num; i++)
{
printf("\nEnter Element %d: ", i+1);
scanf("%d",&M[i]); //accepts the input from the user and stores in array M
}
printf("\nEnter the element to be searched: ");
scanf("%d", &ele); //Accepts the element to be searched from the user
for(i=0;i<num;i++){
/* Check if the element to be searched is equal to the value stored in the array */
if(M[i] == ele){
/* Display the position of the element in the array */
printf("\nElement is found at position %d",i+1);
getch(); //wait until a key is pressed
exit(1);
}
}
printf("\nElement not found");
getch();
}

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