Check if items in an array are consecutive but WITHOUT SORTING in JavaScript

We are required to write a JavaScript function that takes in an array of Numbers as the first argument and a number, say n, as the second argument.

Our function should check if there is a sequence of n (taken as the second argument) or more consecutive numbers in the array but without sorting the array.

For example, if our input array is −

const arr = [0, 4, 6, 5, 9, 8, 9, 12];
const n = 3;

Then our function should return true because there exist three consecutive numbers 4, 5, and 6 in the array.

Example

The code for this will be −

const arr = [0, 4, 6, 5, 9, 8, 9, 12];
const n = 3;
const findSequence = (arr, num) => {
   if(num > arr.length){
      return false;
   };
   let count = 1;
   for(let i = 0; i < arr.length; i++){
      let el = arr[i];
      while(arr.includes(++el)){
         count++;
         if(count === num){
            return true;
         };
      };
      count = 1;
   };
   return false;
};
console.log(findSequence(arr, n));
console.log(findSequence(arr, 4));

Output

And the output in the console will be −

true
false

AmitDiwan

Published on 23-Nov-2020 09:55:23

• Related Questions & Answers
• Check if array elements are consecutive in Python
• Check if three consecutive elements in an array is identical in JavaScript
• Sorting Array without using sort() in JavaScript
• Fetch Second minimum element from an array without sorting JavaScript
• Count unique elements in array without sorting JavaScript
• JavaScript to check consecutive numbers in array?
• Check if Queue Elements are pairwise consecutive in Python
• Sorting an array by date in JavaScript
• Sorting an array by price in JavaScript
• Alternative sorting of an array in JavaScript
• JavaScript - Check if array is sorted (irrespective of the order of sorting)
• Sorting an integer without using string methods and without using arrays in JavaScript
• Sorting an array of objects by an array JavaScript
• Sorting an associative array in ascending order - JavaScript
• Sorting an array that contains undefined in JavaScript?