codility max counters 100% correct javascript solution

Codility Max Counters 100% Javascript Solution

Ok the Max Counters problem is the first algo challenge marked as medium in the codility lessons.

I devised a O(m+n) solution.

We first check if there’s no element N+1 in the array we just run the through the array and increment the counters at the end.

For the case when N+1 is present in the array, we run through the array increasing the counters while A[K] = X < N+1. We keep in the variable max the maximum available counter for the moment when we will have to update all.

When N+1 is met we update all counters to the max value. If the next element is again N+1 we just continue the iteration, as we don’t have a new counter to update since there was no incrementation since the last update.

The Javascript Solution:

function solution(N, A) {
 let  counters = Array (N).fill(0)
    //take care of the case when there is no element === N+1
    //simply run through the array and return the counters at the end
    if (A.indexOf(N+1) === -1){
        for (let j = 0; j < A.length; j++){
        return counters

    let max = min = maxSum = 0
    let nextSkip = 0
    for (let i = 0; i < A.length; i ++){
        if (A[i] < N + 1){
            nextSkip = 0
            //we check and keep a record of the max counter
            if (counters[A[i]-1] > max) {
                max = counters[A[i]-1]
        } else if (A[i] === N + 1 && nextSkip === 0){
            nextSkip = 1
            for (let j =0; j < counters.length; j++){
                counters[j] = max
    return counters

Here is the report.

Did you find a better solution? Let me know in the comments!

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