# Check if Array Elements are Consecutive

If you want to practice data structure and algorithm programs, you can go through 100+ data structure and algorithm programs.

In this post, we will see how to check if array elements are consecutive.

## Problem

Given an array, we need to check if array contains consecutive elements.
For example:

Input: array[] = {5, 3, 4, 1, 2}
Output: true
As array contains consecutive elements from 1 to 5
Input: array[] = {47, 43, 45, 44, 46}
Output: true
As array contains consecutive elements from 43 to 47
Input: array[] = {6, 7, 5, 6}
Output: false
As array does not contain consecutive elements.

## Solution

Simple solution will be to sort the array and check if elements are consecutive just by iterative over array but time complexity of this solution will be o(n^logn).

Can we do better?
Yes, we can do better

• Find minimum and maximum element in the array.
• Check if max-min+1==n, if elements are consecutive then this condition should meet.
• Create a visited boolean array.
• Iterate over the array and check
• visited[arr[i]-min] is true, then return false as elements are repeated.
• mark the element visited.

### Program to check if Array Elements are Consecutive

When you run above program, you will get below output:

Array elements are consecutive

Time complexity of this solution is o(n).

That’s all about how to check if Array Elements are Consecutive.

import_contacts

## Related Posts

• 18 June

### Maximum Number of Vowels in a Substring of Given Length

Table of ContentsApproach – 1 Generate All Substrings Using substring() MethodApproach – 2 Using Sliding Window Method (Linear Time Solution) In this article, we will look at an interesting problem related to the Strings and [Sliding-Window Algorithm](https://java2blog.com/sliding-window-maximum-java/ “Sliding-Window Algorithm”). The problem is : "Given a String we have to Find the Maximum Number of Vowel […]

• 04 June

### Search for a range Leetcode – Find first and last position of element in sorted array

Table of ContentsApproach 1 (Using Linear Search)Approach 2 (Using Modified Binary Search-Optimal) In this article, we will look into an interesting problem asked in Coding Interviews related to Searching Algorithms. The problem is: Given a Sorted Array, we need to find the first and last position of an element in Sorted array. This problem is […]

• 30 April

### Convert Postfix to Infix in Java

Learn about how to convert Postfix to Infix in java.

• 30 April

### Convert Prefix to Postfix in Java

Learn about how to convert Prefix to Postfix in java.

• 16 April