Searching Techniques Linear Search in C

A file is a collection of records and a record is in turn a collection of 
fields. A field,which is used to differentiate among various records, is 
known as a ‘key’. 

Algorithm
 Here, m represents the unordered array of elements
 n represents number of elements in the array and
 el represents the value to be searched in the list

Step 1: [Initialize]
        k=0
        flag=1
Step 2: Repeat step 3 for k=0,1,2…..n-1
Step 3: if (m[k]=el )
        then
        flag=0
        print “Search is successful” and element is found at location (k+1)
        stop
        endif
Step 4: if (flag=1) then
        print “Search is unsuccessful”
        endif

/*Program for Linear Search*/

/*Header Files*/

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

/*Global Variables*/

int search;

int flag;

/*Function Declarations*/

int input(int *, int, int);

void linear_search(int *, int, int);

void display(int *, int);

/*Functions */

void linear_search(int m[], int n, int el) {
   int k;
   flag = 1;
   for (k = 0; k < n; k++) {
      if (m[k] == el) {
         printf("\nSearch is Successful");
         printf("\nSearch is Successful2");
         printf("Element : %i Found at location :%i", el, k + 1);
         flag = 0;
      }
   }

   if (flag == 1) {
      printf("\n Search is unsuccessful");
   }
}

void display(int m[], int n)

{
   int i = 0;

   for (i = 0; i < 20; i++)

   {
      printf("\n%d", m[i]);
   }
}

int input(int m[], int n, int el)

{
   int i;

   n = 20;

   el = 83;

   printf("Number of elements in the list : %d", n);

   for (i = 0; i < 20; i++)

   {
      m[i] = rand() % 100;
   }

   printf("\n Element to be searched :%d", el);

   search = el;

   return n;
}

/*Main Function*/

void main()

{
   int n, el, m[200];

   int number = input(m, n, el);

   el = search;

   printf("\n Entered list as follows: \n");

   display(m, n);

   linear_search(m, number, el);

   printf("\n In the following list\n");

   display(m, n);
}