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Backend Developer was asked...14 August 2015

What is polymorphism?

20 Answers

Polymorphism means having many forms. In object-oriented programming paradigm, polymorphism is often expressed as 'one interface, multiple functions'. Less

Polymorphism means having many forms. In object-oriented programming paradigm, polymorphism is often expressed as 'one interface, multiple functions'. Less

Polymorphism means having many forms. In object-oriented programming paradigm, polymorphism is often expressed as 'one interface, multiple functions'. Less

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Outreach

Behavioral Why outreach The impact you hope to have from your next role?What is most important factor in your career/job What do you think about RSpec? How do you compare it with other frameworks What was the hardest/Challenging technical problem you faced and how did you resolve it Coding This problem concerns finding a time when we can do daily recurring maintenance on a server. You are to write a function that is given the following information: List of times when the server is busy every day Duration, in minutes, of the desired maintenance window The function should return the start time of a daily maintenance window when the server is not busy. In pseudo-code, the function signature would look something like this: maintWindowStart(busyTimes, durationMins) -> startTime The "busy times" should be time ranges like the following, and can be represented in whatever data structure you feel is appropriate. 0:05 to 0:30 = [5, 30] 2:00 to 4:01 = [120, 241] 13:10 to 16:55 = [790, 1015] [[5, 30], [120, 541], [790, 1015]] // requested duration -> expected start time // 10 -> 30 // 120 -> 541 // 4 -> 0 // 300 -> 1015

6 Answers

I am sorry, I didn't meant to comment here!! It was wrong copy & paste error

how long does it take to get an answer from Outreach after the onsite?

I got the same question... which I solved... but interviewer did not clear the question in the beginning.. now waiting for the response. Less

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Agoda

algorithm question, competition programming

6 Answers

What kind of algorithms questions they ask are they of hackerearth or geekforgeek level I mean top coding websites. I wanna know the level of difficulty Less

Can you elaborate more on these? What kind of algorithm questions did they ask? and what do you mean by competition programming? do you mean that your interview process was similar to competition programming? Less

I meant they are kind of questions that you can find on hackerrank or top coder sites Less

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Walkover Web Solutions

Given a string s="my name is anny" print it in this manner: m n i a y a s n m m e y ie first letter of every word in the string

5 Answers

$str = "my name is anny"; $str_arr = explode(" ", $str); $len = count($str_arr); $w = 0; $max = max(array_map('strlen' , $str_arr)); while($w "; endwhile; ?> Less

I was trying to give answer twice of this problem but glasdoors validation removes some part of my code Less

I would simply write an algorithm

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HelloFresh

Make recipe APIs for HelloFresh

5 Answers

You can get the full application in Dhiraj Patra github repo.

Not gonna lie, your code is pretty bad, no separations of concerns, no contextual logging. The position was for a senior engineer, your stuff is junior level at best. Don't lash people out for your inadequacy of the role. Less

Sorry but I have to be honest, your code is pretty bad. To me the true is, you are not good enough and that's it. You also were very anti ethical exposing the whole code challenging to your Github Less

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Shopee

How to reverse a space-delimited-string word by word

4 Answers

1) Split string into words 2) convert problem into, how to reverse a word 2.1) convert word into an array 2.2) reverse array 3) join back each individual problem Less

> loop starting from the last element It's not reverse a sentence. But reverse words in a sentence. I.e. ABC Def hij --> CBA fed jih Less

do with double linked list so only need one loop is enough. O(n)

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Home24

whats the angle between the minute pointer and hour pointer at 3:15

4 Answers

at 3:15 hour arrow will indicate to 16minutes. So diff is 1 minute = 360/60 = 6 deg Less

U r right, it's 7.5 =) I was wrong and sleepy

Angle

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Tinder

Find the max k elements in an unsorted array.

4 Answers

Build maxheap and extract first k elements

The best way would be to use the common rank finding algorithm. Find the rank # of elements - k. In the step where k is found look to the right and those are the tops. O(n) time. Less

You could sort but there is a more efficient way. You could use a priority queue or have an array of length of k, copy the first k elements of the array, sort them and then read the rest of the elements of the original array and swap elements as necessary. Less

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Zalando

Given an integer, re-arrange the integer such that first and last digit will be at first and second, second and second last digit will be at third and fourth position from left of the re-arranges integer and so on. Example: Input -> 12345678, Output -> 18273645 Input -> 1234567, Output -> 1726354

3 Answers

static int[] reArrangeMinToMax (int[] ar){ int[] arranged = new int [ar.length]; int small=0; int large=ar.length-1; for (int i=0; i Less

package Java8; import java.util.Arrays; public class rearrangeMinAndMax { public static void main(String[] args) { // TODO Auto-generated method stub int[] arr= {1,2,3,4,5}; Solution(arr); } static void Solution(int[] number) { int[] arr = new int [number.length]; int mid,j,k=0; if((number.length%2)==0) { mid=number.length/2; } else { mid=(number.length -1)/2; arr[number.length-1]=number[mid]; } for(int i=0;imid;j--) { arr[k]=number[j]; k=k+2; } System.out.println(Arrays.toString(arr)); } } Less

static int[] reArrangeMinToMax (int[] ar){ int[] arranged = new int [ar.length]; int small=0; int large=ar.length-1; for (int i=0; i Less

Monzo Bank

How does some technical stuff work

3 Answers

It's a long and complex chat. But it was really fun.

How long did it take them to send the final rejection email?

What technical stuff in particular?

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