Linear Search in Java

public class LinearSearchExample{    
public static int linearSearch(int[] arr, int key){    
        for(int i=0;i<arr.length;i++){    
            if(arr[i] == key){    
                return i;    
            }    
        }    
        return -1;    
    }    
    public static void main(String a[]){    
        int[] a1= {10,20,30,50,70,90};    
        int key = 50;    
        System.out.println(key+" is found at index: "+linearSearch(a1, key));    
    }    
}    

Output:

50 is found at index: 3

Linear Search in Java (Another way)

You can also use a method where array is not predefined. Here, user has to put the elements as input and select one element to check its location.

import java.util.Scanner;  
   
class LinearSearchExample2   
{  
  public static void main(String args[])  
  {  
    int c, n, search, array[];  
   
    Scanner in = new Scanner(System.in);  
    System.out.println("Enter number of elements");  
    n = in.nextInt();   
    array = new int[n];  
   
    System.out.println("Enter those " + n + " elements");  
   
    for (c = 0; c < n; c++)  
      array[c] = in.nextInt();  
   
    System.out.println("Enter value to find");  
    search = in.nextInt();  
   
    for (c = 0; c < n; c++)  
    {  
      if (array[c] == search)     /* Searching element is present */  
      {  
         System.out.println(search + " is present at location " + (c + 1) + ".");  
          break;  
      }  
   }  
   if (c == n)  /* Element to search isn't present */  
      System.out.println(search + " isn't present in array.");  
  }  
}  

Output:

Use image LinearSearchExample