Open In App

Elements greater than the previous and next element in an Array

Last Updated : 08 Mar, 2022
Comments
Improve
Suggest changes
Like Article
Like
Report

Given an array of N integers. The task is to print the elements from the array which are greater than their immediate previous and next elements.
Examples
 

Input : arr[] = {2, 3, 1, 5, 4, 9, 8, 7, 5}
Output : 3, 5, 9
In above given example 3 is greater than its 
left element 2 and right element 1. 
Similar logic is applied to other elements 
hence our final output is 3, 5, 9.

Input : arr[] = {1, 2, 3, 2, 1}
Output : 3


 


Approach: Since there is no element on the left of the first element(arr[0]) and there is no element to the right of last element(arr[N-1]) so these two elements will be excluded from the final answer.
Now, traverse the array starting from the index 1 to N-2 and for every element arr[i] check if arr[i] > arr[i-1] and arr[i] > arr[i+1].
Below is the implementation of the above approach: 
 

C++
// C++ program to print elements greater than
// the previous and next element in an Array
#include <bits/stdc++.h>
using namespace std;

// Function to print elements greater than
// the previous and next element in an Array
void printElements(int arr[], int n)
{
    // Traverse array from index 1 to n-2
    // and check for the given condition
    for (int i = 1; i < n - 1; i++) {
        if (arr[i] > arr[i - 1] and arr[i] > arr[i + 1])
            cout << arr[i] << " ";
    }
}

// Driver Code
int main()
{
    int arr[] = { 2, 3, 1, 5, 4, 9, 8, 7, 5 };
    int n = sizeof(arr) / sizeof(arr[0]);

    printElements(arr, n);

    return 0;
}
Java
// Java program to print elements greater than 
// the previous and next element in an Array 
class GfG 
{ 

// Function to print elements greater than 
// the previous and next element in an Array 
static void printElements(int arr[], int n) 
{ 
    // Traverse array from index 1 to n-2 
    // and check for the given condition 
    for (int i = 1; i < n - 1; i++)
    { 
        if (arr[i] > arr[i - 1] && arr[i] > arr[i + 1]) 
            System.out.print(arr[i] + " "); 
    } 
} 

// Driver Code 
public static void main(String[] args) 
{ 
    int arr[] = { 2, 3, 1, 5, 4, 9, 8, 7, 5 }; 
    int n = arr.length; 

    printElements(arr, n); 
} 
} 

// This code is contributed by Prerna Saini
Python3
# Python 3 program to print elements greater than
# the previous and next element in an Array

# Function to print elements greater than
# the previous and next element in an Array
def printElements(arr, n):
    
    # Traverse array from index 1 to n-2
    # and check for the given condition
    for i in range(1, n - 1, 1):
        if (arr[i] > arr[i - 1] and 
            arr[i] > arr[i + 1]):
            print(arr[i], end = " ")

# Driver Code
if __name__ == '__main__':
    arr = [2, 3, 1, 5, 4, 9, 8, 7, 5]
    n = len(arr)

    printElements(arr, n)
    
# This code is contributed by
# Surendra_Gangwar
C#
 using System;

// c# program to print elements greater than 
// the previous and next element in an Array 
public class GfG
{

// Function to print elements greater than 
// the previous and next element in an Array 
public static void printElements(int[] arr, int n)
{
    // Traverse array from index 1 to n-2 
    // and check for the given condition 
    for (int i = 1; i < n - 1; i++)
    {
        if (arr[i] > arr[i - 1] && arr[i] > arr[i + 1])
        {
            Console.Write(arr[i] + " ");
        }
    }
}

// Driver Code 
public static void Main(string[] args)
{
    int[] arr = new int[] {2, 3, 1, 5, 4, 9, 8, 7, 5};
    int n = arr.Length;

    printElements(arr, n);
}
}
PHP
<?php
// PHP program to print elements greater than
// the previous and next element in an Array

// Function to print elements greater than
// the previous and next element in an Array
function printElements($arr, $n)
{
    // Traverse array from index 1 to n-2
    // and check for the given condition
    for ($i = 1; $i < $n - 1; $i++) 
    {
        if ($arr[$i] > $arr[$i - 1] and
            $arr[$i] > $arr[$i + 1])
            echo $arr[$i] . " ";
    }
}

// Driver Code
$arr = array(2, 3, 1, 5, 4, 9, 8, 7, 5);
$n = sizeof($arr);

printElements($arr, $n);

// This code is contributed
// by Akanksha Rai
JavaScript
<script>

// Javascript implementation of the approach 

// Function to print elements greater than
// the previous and next element in an Array
function printElements(arr,  n)
{
    // Traverse array from index 1 to n-2
    // and check for the given condition
    for (var i = 1; i < n - 1; i++) {
        if (arr[i] > arr[i - 1] && arr[i] > arr[i + 1])
            document.write( arr[i] + " ");
    }
}
var arr = [ 2, 3, 1, 5, 4, 9, 8, 7, 5 ];
var n = arr.length;

printElements(arr, n);

// This code is contributed by SoumikMondal

</script>

Output: 
3 5 9

 

Time Complexity : O(n)
Auxiliary Space : O(1)


Next Article
Article Tags :
Practice Tags :

Similar Reads