Day26 - Searching in java: (Linear Search or (Sequential Search in Java)

searching in java:

==> In Java,searching refers to the process of finding an element in a data structure like an array,list,or map.

==> Let’s break down the main types of searching techniques:

Linear Search (Sequential Search):

Definition:

==> Linear search is a simple search algorithm where each element is checked one by one until the target is found or the end of the array is reached.

Time Complexity:

Best case:

==> O(1) — if the target is at the first index.

Worst case:

==> O(n) — if the target is at the last index or not found.

Use case:

==> Works well for small or unsorted datasets.

Example program:(While loop)

package javaprogram;

public class Linearsearch {

public static void main(String[] args) {
// TODO Auto-generated method stub

int[] arr= {10,15,8,11,55,67,7}; //0 1 2 3 4 5 6
int key=7;
int ke=8;
int i=0;

while(true)   //looping  // while(i<arr.length)  
{
if(arr[i]==key)   // if condition
{
System.out.println("key is presented:"+""+i);  //print statement
break;
}

if(arr[i]==ke)    // if condition
{
System.out.println("ke is presented:"+""+i);  //print statement
//break;
}
i++;
}
}
}

Output:

Ex program:

package javaprogram;

public class Linearsearch1 {
public static void main(String[] args) {

// TODO Auto-generated method stub

int[] arr= {10,15,8,11,55,67,7}; //0 1 2 3 4 5 6
int key=7;
if(arr[0]==key)

{
System.out.println("key is presented"+" "+ 0);  //print statement

}
if (arr[1]==key)
{
System.out.println("key is presented"+" "+ 1);
}
if (arr[2]==key)
{
System.out.println("key is presented"+" "+ 2);
}
if (arr[3]==key)
{
System.out.println("key is presented"+" "+ 3);
}
if (arr[4]==key)
{
System.out.println("key is presented"+" "+ 4);
}
if (arr[5]==key)
{
System.out.println("key is presented"+" "+ 5);
}
if (arr[6]==key)
{
System.out.println("key is presented"+" "+ 6);
}
}
}

Output: