• Skip to primary navigation
  • Skip to content
  • Skip to primary sidebar
  • Skip to secondary sidebar

GoHired

Interview Questions asked in Google, Microsoft, Amazon

Join WeekEnd Online Batch from 4-April-2020 on How to Crack Coding Interview in Just 10 Weeks : Fees just 20,000 INR

  • Home
  • Best Java Books
  • Algorithm
  • Internship
  • Certificates
  • About Us
  • Contact Us
  • Privacy Policy
  • Array
  • Stack
  • Queue
  • LinkedList
  • DP
  • Strings
  • Tree
  • Mathametical
  • Puzzles
  • Graph

Facebook Interview Question : Interleave List

May 14, 2018 by Dhaval Dave

Interleave List If input = [[1,2,3], [9, 0], [5], [-4,-5,-2,-3,-1]] then output = [1,9,5,-4,2,0,-5,3,-2,-3,-1];
Asked in Facebook F2F

Interleave List
Interleave List

In Python you can do it very easily

#!/usr/bin/python

max = 3
listofList = [[1, 2, 3], [9, 5], [-1], [12,90,3] ];
oplist =[];
for i in range(0,max):
    for list in listofList:
       if (i < len(list)):
           oplist.append(list[i])
print oplist

In Java using same logic..

import java.util.*;
import java.lang.*;
import java.io.*;
import java.util.Arrays;
import java.util.List;

class Ideone
{
	private static void interleaveLists(List<List<Integer>> ll){
    	if(ll == null)
    	    return;
    	int listLength = 0;
    	int total = 0;
    	for(List<Integer> list : ll){
	  if(list == null)
	    continue;
	  listLength = Math.max(list.size(), listLength);
	  total += list.size();
    	}
    	int[] result = new int[total];
    	int index = 0;
    	for(int i = 0; i < listLength; ++i){
    	  for(List<Integer> list : ll){
    	    if(list == null)
    	      continue;
                  if(i < list.size()){
    		result[index++] = list.get(i);
    		System.out.println(list.get(i));
    	      }
      	  }
    	}
    	for( int x :result){
    	   System.out.println(x);
    	}

    }
	public static <Integer> List<Integer> twoDArrayToList(int [][] twoDArray) {
	    List list = new ArrayList();
	    for (int [] array : twoDArray) {
	        list.add(Arrays.asList(array));
	    }
	    return list;
	}
	public static void main (String[] args) throws java.lang.Exception
	{	
		int [][] arr = {{1, 2, 3}, {9, 0}, {5}, {-4, -5, -2, -3, -1,5,2}};
		List<List<Integer>> ll = twoDArrayToList(arr);
		interleaveLists(ll);
	}
}

Similar Articles

Filed Under: Algorithm, Data Structure, Facebook Tagged With: 2d matrix, Array, Linked List

Reader Interactions

Primary Sidebar

Join WeekEnd Online/Offline Batch from 4-April-2020 on How to Crack Coding Interview in Just 10 Weeks : Fees just 20,000 INR

Join WeekEnd Online/Offline Batch from 4-April-2020

WhatsApp us

Secondary Sidebar

Custom Search

  • How I cracked AMAZON
  • LeetCode
  • Adobe
  • Amazon
  • Facebook
  • Microsoft
  • Hacker Earth
  • CSE Interview

Top Rated Questions

flattens 2 D linked list to a single sorted link list

Word Break Problem

Apriori algorithm C Code Data Mining

LeetCode: Binary Tree Maximum Path Sum

Linked List V/S Binary Search Tree

Find two non repeating elements in an array of repeating elements

Amazon Interview Experience – SDE Chennai

VMWare SDEII Interview

TicTacToe Game As Asked in Flipkart

Password Predictor

HackeEarth Flipkart’s Drone

N teams are participating. each team plays twice with all other teams. Some of them will go to the semi final. Find Minimum and Maximum number of matches that a team has to win to qualify for finals ?

Reversal of LinkedList

Find position of the only set bit

Daughter’s Age VeryGood Puzzle

Get Minimum element in O(1) from input numbers or Stack

LeetCode : Word Search

Amazon Interview On-Campus For Internship – 1

Python Array String

Binary Tree in Java

Find shortest distances between every pair of vertices ( Dynamic Programming Floyd Warshall Algorithm)

Circular Linked List

Diagonal Traversal of Binary Tree

Find Pythagorean Triplets in an array in O(N)

The greedy coins game Dynamic Programming

Generic Object Oriented Stack with Template

Python Dictionaries

Longest Increasing Subsequence

Number of Islands BFS/DFS

Check if an array has duplicate numbers in O(n) time and O(1) space

Copyright © 2026 · Genesis Framework · WordPress · Log in