Finding the index of the first element that violates the series (first non-consecutive number) in JavaScript
We have to write a function that takes in an array and returns the index of the first nonconsecutive number from it.
Like all the numbers will be in an arithmetic progression of common difference 1. But the
number, which violates this rule, we have to return its index. If all the numbers are in perfect
order, we should return -1.
Example
Let’s write the code for this function −
const arr = [1,2,3,4,5,6,8,9,10];
const secondArr = [3,4,5,6,7,8,9,10,11,12,13,14,15];
const findException = (arr) => {
for(let i = 0; i < arr.length-1; i++){
if(arr[i+1] - arr[i] !== 1){
return i+1;
};
};
return -1;
};
console.log(findException(arr));
console.log(findException(secondArr));Output
The output in the console −
6
-1
Published on 17-Oct-2020 14:31:15
