CareerCup

Given one string s1, and then insert one char into this string at any place, to get s2, find the inserted char
Could you do it in logn time

Give you a 2xN board and two kinds of tiles: 1x2 (two squares across), 2x1 (two squares up) Ask how many ways you can fill the board.

**       **       *      *                                      
*         *        **   **

Follow up is the new four kinds of tiles: L shape in different angle, , ask you how many kinds of tiles are now six

give a binary matrix, 0 on behalf of the sea, 1 on behalf of the land, the val also represents the height of the altitude, if a cell is originally on land and is also surrounded by eight neighbor are on land, that cell become 2, each cell and its eight neighbor elevation cannot differ by more than 1. Return to the highest altitude can take altitude (special case is if the entire matrix is 1, then it is unlimited)

In the range of 0-n, return all the numbers that in the reverse can be mistaken for another number. E.g. 18 -> 81. The corner case is not counting the same number, such as 101 and not 0 at the end of the figure such as 60 (because 09 is not 9)
Public List<Integer> getNum(int n)

Given a function that reads 4096 bytes from a file. write a new function which takes in a buffer and the number of bytes to be read from the user and uses the given function to write values into the buffer.

//given
//returns the number of bytes read
private int read4k(int[] buffer, int offset)


//TODO:
// it should return the bytes read
public int readIntoBuffer(int[] buffer, int byteCount);

Give a binary tree, each node has an extra information, that is, how many children he has,
Find the kth node val in the inorder transversal ,
Followup how to insert a node, such that this newly added node become the Nth node of the inorder binary tree's traversal

class TreeNode{
    int val;
    int NumberOfchildren;
    TreeNode left;
    TreeNode right;
    public TreeNode(int val){
        this.val = val;
    }
}
public static int findKthOfInorder(TreeNode root, int k) {

Give a weighted n-nary tree and find the longest path from the root node to the leaf node
    class Node {
        int id;
        // connected node id, edge weight
        Map <Integer, Integer> edges;
    }

Google
1st round
Given a box with N balls in it, each ball having a weight, randomly choose pick one out base on the weight.
Input ball1-> 5kg, ball2 -> 10kg and ball3 -> 35kg,
then Prob(ball1 chosen) = 10%, Prob(ball2) = 20%,
Prob(ball3) = 70% ;

Follow-up:
Select a ball randomly based on weights. Once a ball is chosen, remove it. Next time select from the remaining balls. Go on until there is nothing left in the box.

Given a binary matrix, count the number of square that can be formed by all 0s

given a string p, called order, such as abc, means a in front of b, and so on
given a second string s, to determine whether it is follow the order of p, return boolean,
example If aaa return true,
If cba is false
If aaxyc is true, the letters that have not been seen in the order are skipped

Find whether string S is periodic.
Periodic indicates S = nP.
e.g.
S = "ababab", then n = 3, and P = "ab"
S = "xxxxxx", then n = 1, and P = "x"
S = "aabbaaabba", then n = 2, and P = "aabba"

follow up:
Given string S, find out the P (repetitive pattern) of S.

Given a string as a datastream Iterator<Character>, find the length of the longest substring without repeating characters

public String longestUniqueChars(Iterator<Character> chars)

Giving start string and end string, determine if start string can finally reach to the same as end string with below rules.
For example:
"R L _ _ L R L"
"_": the space is empty
"L": this can only swap with the empty letter _ on its left side
"R": this can only swap with the empty letter _ on its right side
So, "R L _ _ L R L" can change to "R L _ L _ R L" , and can continue change to (if you want) "R L L _ _ R L". from: 1point3acres.com/bbs
The question is given these rules and the start string and end string, could we change the start string to end string (unlimited # moves as long as it is valid).
For example:
"R _ _ L R _ R _L"
can be changed to
"_ R L _ _ R R L _"

Round3 Google
For N light bulbs , implement two methods
I. isOn(int i) - find if the ith bulb is on or off.
II. toggle(int i, int j) - i <= j. Switch state (switch on if it's off, turn off if it's on) of every bulb in range i to j.
All bulbs are off initially.

given a list of points in a rectangular coordinate system, seeking any two points, such that all the remaining points will be in only one side of the line.

Give a string, finds all duplicate substrings of length k

Give an array such as [1,2,2,2,0] every time you can jump 1 to a [i] step,
If you can jump to 0, return false
if you go out to return true

A group of people goes to eat together, each pay is not the same, then after they go home later, they each use mutual transfer so that everyone pay the same money.
input is an int array that each person pay, Ask who the amount of money was paid when the transfer was done, such as B -> A $ 3, C -> A $ 1.

/**
* Google
* Given a list of non-negative numbers and a target integer k,
* write a function to check if the array has a continuous subarray of size at least 2 that sums up to the multiple of k, that is, sums up to n*k where n is also an integer.
**/

find the last index of the last duplicate number in a sorted array

ex
input: 1,2,5,6,6,7,9
output: 4(index)

Given a string, check if it is can be reorganized such that the same char is not next to each other, If possible, output a possible result
example
input: google
one possible output: gogole

Given a dictionary, generate the shortest string, both palindrome and pangram.
Each word can be used only once and unlimited words can be used.

Give you a pattern (digit in the pattern matches the corresponding
number of letters,
letter means match the letter itself),
a string to determine whether match:
ex:
abc -> 'abc' true
'1oc3' -> 'aoczzz', 'bocabc' true

Google
Given an array a[] and an integer k, a[i] means flower at position a[i] will blossom at day i. Find the first day that there are k slots between two blooming flowers.

assuming there is a freeway, n cars on the road, each car has a different integer speed, but are in the 1-n range. Now give you an array that represents the speed of each car. The starting order of the vehicle is the order of the array, ask the final formation of several clusters, the size of each cluster is how much? It can be understood that, although the vehicle speed is different, but even behind the car faster than the previous car, because you cannot pass, the last must only travel at the speed of the previous car, which formed a cluster. For example [2,4,1,3], finally [2,4] is a cluster, [1,3] is a cluster.

Follow up is now suppose you want to add a car, the speed of the car than other large, but not sure the car's starting order, so that the final output of each possible cluster (List of List). Requirements can be adjusted and call the previous function, but can only be called once

There is a stream of data <Symbol, timestamp, price>, and possibly also Correction Data <Symbol, timestamp, price> and then addData (symbol, timestamp, price) and correctData , Update minPrice, maxPrice, recentPrice in these two functions.

Give you a bunch of data <key, value, expiredTime>, design a data structure storage.
About the idea, based on Map solution.
class NewMap {
Map <Integer, Integer> data = new HashMap <> (); // store key-value pairs
Map <Integer, Integer> expired = new HashMap <> (); // store key-expired pairs
}


Then implement the three functions get (), put (), expire ().

how to implement the standard JSON.stringify and JSON.parse method

design a zigzag iterator, implement the prev() and hasPrev function

Fibonacci asked if you want to query 1-2 ^ 32 any one but the memory can only remember 2 ^ 20 number of how to do O (1) query