SDE - Intern

You are given the schedule of 'N' meetings with their start time 'Start[i]' and end time 'End[i]'.

You have only 1 meeting room. So, you need to return the maximum number of meetings you can organize.

Note:

The start time of one chosen meeting can’t be equal to the end time of the other chosen meeting.

For example:

'N' = 3, Start = [1, 3, 6], End = [4, 8, 7].

You can organize a maximum of 2 meetings. Meeting number 1 from 1 to 4, Meeting number 3 from 6 to 7.

You are given an array “nums” of size N. Your task is to find the length of the longest subsequence of array “nums” such that the absolute difference between every adjacent element in the subsequence is one.

For Example:

If “nums” = {2, 1, 3}.

The valid non-empty subsequences of the array are {2}, {1}, {3}, {2, 1}, {1, 3}, {2, 3} and {2, 1, 3}. So, the longest subsequence satisfying the given conditions are {2, 1} and {2, 3}. The length of the longest subsequence is 2. So, the answer is 2.

The subsequence of an array is a sequence of numbers that can be formed by deleting some or no elements without changing the order of the remaining elements. For example, if the given array “nums” = {1, 2, 5, 4, 8}, then {1, 2, 5, 4, 8}, {1, 5, 8}, {2} are some of the valid subsequences whereas the sequence {4, 2} is not a valid subsequence as the order of the elements differ from the original array.

Note:

Any subsequence of length = 1 is also a valid subsequence.

Ninjaland is a country having 'N' states numbered from 1 to 'N'. These 'N' states are connected by 'M' bidirectional roads. Each road connects to different states and has some cost to travel from one state to another. Now, the chief wants you to select 'N' - 1 roads in such a way that the tourist bus can travel to every state at least once at minimum 'COST'.

For example :

Consider a country having 4 states numbered from 1 to 4. These 4 states are connected by 5 bidirectional roads given as :
1 --- 2 with cost = 8
2 --- 3 with cost = 6
3 --- 4 with cost = 5
1 --- 4 with cost = 2
1 --- 3 with cost = 4

The map of the country can be represented as:

Now, the best way to choose 3 roads is:

The cost of travelling from any state to all other states is  2 + 4 + 6 i.e. 12.

You have been given a string ‘S’. You need to return the lexicographically smallest subsequence of ‘S’ that contains all the distinct characters of ‘S’ exactly once. Return the string as mentioned above.

A string is a subsequence of a given string, that is generated by deleting some character of a given string without changing its order.

Example:

Let S = “ababc”. The lexicographically smallest subsequence containing all the distinct characters of strings is “abc”. 

Note:

Strings consist of only lowercase characters.

You do not need to print anything; it has already been taken care of. Just implement the function.

Kevin has given you a Singly Linked List that contains only integers. You have to determine if it forms a cycle or not.

A cycle occurs when a node's next pointer points back to a previous node in the list.

You are given a doubly-linked list with 'N' nodes, rotate the linked list counter-clockwise by 'K' nodes. 'K' is a positive integer and is smaller than the number of nodes in the linked list, that is 'N'.

A doubly linked List (DLL) contains an extra pointer, called the previous pointer, together with the next pointer and data which are there in the singly linked list such that both forward and backward navigation is possible.

For example

The given linked list is - 

If K = 3, then the list after rotating it by K nodes is:

Note:

1. The value of any node in the linked list will not be equal to -1.

You have been given a Snake and Ladder Board with 'N' rows and 'N' columns with the numbers written from 1 to (N*N) starting from the bottom left of the board, and alternating direction each row.

For example

For a (6 x 6) board, the numbers are written as follows:

You start from square 1 of the board (which is always in the last row and first column). On each square say 'X', you can throw a dice which can have six outcomes and you have total control over the outcome of dice throw and you want to find out the minimum number of throws required to reach the last cell.
Some of the squares contain Snakes and Ladders, and these are possibilities of a throw at square 'X':
You choose a destination square 'S' with number 'X+1', 'X+2', 'X+3', 'X+4', 'X+5', or 'X+6', provided this number is <= N*N.
If 'S' has a snake or ladder, you move to the destination of that snake or ladder.  Otherwise, you move to S.
A board square on row 'i' and column 'j' has a "Snake or Ladder" if board[i][j] != -1. The destination of that snake or ladder is board[i][j].

Note :

You can only take a snake or ladder at most once per move: if the destination to a snake or ladder is the start of another snake or ladder, you do not continue moving - you have to ignore the snake or ladder present on that square.

For example, if the board is:
-1 1 -1
-1 -1 9
-1 4 -1
Let's say on the first move your destination square is 2  [at row 2, column 1], then you finish your first move at 4 [at row 1, column 2] because you do not continue moving to 9 [at row 0, column 0] by taking the ladder from 4.

A square can also have a Snake or Ladder which will end at the same cell.
For example, if the board is:
-1 3 -1
-1 5 -1
-1 -1 9
Here we can see Snake/Ladder on square 5 [at row 1, column 1] will end on the same square 5.