Linear Search also called sequential search in data structure which works by scanning one by one element in the list until the searched element is found.
For Example:
If we want to search 30 in the following Array:
Step-1 : Firstly, 30 is compared to first element that is 10
Step-2: When not matched then 30 is compared to second element that is 20
Step-3 When not matched then 30 is compared to third element that is 30
Step -4: Finally element is found
Advantage of Linear Search over Binary Search
- Applicable for Small data
- Can be used for unsorted array
- Easy to understand
- No special data structure required
Disadvantage
- Time Consuming
- Not applicable for Large data
Applications of linear Search in real life
- Phonebook
- Books like novel
- movie
Linear Search Program in C++
Program of Searching in C++ is as follows:
#include<iostream>
#include<stdio.h>
#include<stdlib.h>
using namespace std;
int main() {
int list[100];
int i,n,pos,x;
char ch;
do {
cout<<"\n Enter the size of the list(no. of elements): ";
cin>>n;
cout<<" \n Enter the elements: ";
for(i=0;i<n;i++) {
cin>>list[i];
cout<<" ";
}
pos=-1;
cout<<"\n Enter the element to be searched: ";
cin>>x;
//searching the list sequentially from here.
for(i=0;i<n;i++) {
if(list[i]==x)
pos=i;
}
if(pos>-1) {
cout<<"\n Element Found";
cout<<"\n The Position of element is: "<<pos<<" \n\n";
}
else
cout<<"\n Sorry!!!Search is Unsuccessful!!!\n ";
cout<<"\n Want to try again(y/n): ";
cin>>ch;
} while(ch=='y'||ch=='Y');
return 0;
}Output of the program to find the number in the list using c++ :
Linear Search Program in C++ Using Array
Group of element in any form of data structure is an array.
Program of searching in C++ using array as follows:
#include<iostream>
#include<conio.h>
using namespace std;
int main(){
int i,data,found=-1,a[10];
cout<<"enter 10 numbers in array\n";
for(int i=0;i<10;i++)
cin>>a[i];
cout<<"\nenter number to be search\n";
cin>>data;
for(i=0;i<10;i++) {
if(a[i]==data) {
found=i;
break;
}
}
if (found > -1 )
cout<<"data is present at position\n"<<found;
else
cout<<"data is not present";
getch();
}Output of the program to find the number in the array using c++ :
Linear Search Program in C using Recursion
The program in which one function works repeatedly to do similar work until it complete is called as recursion.
Program of linear search in C as follows:
#include <stdio.h>
int RecursiveLS(int arr[], int value, int index, int n)
{
int pos = 0;
if(index >= n)
return 0;
else if (arr[index] == value)
{
pos = index + 1;
return pos;
}
else
return RecursiveLS(arr, value, index+1, n);
return pos;
}
int main()
{
int n, value, pos, m = 0, arr[100];
printf("Enter the total elements in the array ");
scanf("%d", &n);
printf("Enter the array elements\n");
for (int i = 0; i < n; i++){
scanf("%d", &arr[i]);
}
printf("Enter the element to search ");
scanf("%d", &value);
pos = RecursiveLS(arr, value, 0, n);
if (pos != 0)
{
printf("Element found at pos %d ", pos);
}
else
{
printf("Element not found");
}
return 0;
}
Output the program in C using recursion which is as follows:
Linear Search Program in Python
In this program the number is search using python language is as follows:
def linear_search(alist, key):
"""Return index of key in alist. Return -1 if key not present."""
for i in range(len(alist)):
if alist[i] == key:
return i
return -1
alist = input('Enter the list of numbers: ')
alist = alist.split()
alist = [int(x) for x in alist]
key = int(input('The number to search for: '))
index = linear_search(alist, key)
if index < 0:
print('{} was not found.'.format(key))
else:
print('{} was found at index {}.'.format(key, index))Output of the program to search a number using python is as follows:
Related Link: