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# Count of pairs in an array that have consecutive numbers using JavaScript

## Problem

We are required to write a JavaScript function that takes in an array of integers. Our function should return the count of such contagious pairs from the array that have consecutive numbers in them.

## Example

Following is the code −

const arr = [1, 2, 5, 8, -4, -3, 7, 6, 5]; const countPairs = (arr = []) => { let count = 0; for (var i=0; i<arr.length; i+=2){ if(arr[i] - 1 === arr[i+1] || arr[i] + 1 === arr[i + 1]){ count++; }; }; return count; }; console.log(countPairs(arr));

## Output

3

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