SDE - 1

You are given an integer of array/list 'ARR' of length ‘N. You are supposed to return true if it is possible to construct at least one non-degenerate triangle using values of array/list as sides of the triangle, otherwise, return false.

A board can be divided in two halves which are to be given to two players and then you need to add ships for each players. Every player will get a chance to hit at any random point by missile and if it hits the opponent's ship, the ship will get destroyed. The players wins if all ships of its opponent are destroyed. Restrictions - You can hit missile at the same point two times in a game

Some players are put inside an ‘N’ x ‘M’ matrix ‘GRID’ one by one where:

• ‘.’ represents an empty cell.
• ‘#’ represents a wall.
• ‘@’ represents the starting point.
• Lowercase letters represent keys.
• Uppercase letters represent locks.

The player to collect all the keys in minimum moves will win the game. The ninja is one of the players and needs your help to win the game. He wants you to find the minimum number of moves to get all the keys. The rules of the game are:

• You have to start from the starting point and move in one of the four cardinal directions.
• You cannot walk outside the grid or walk into a wall. You can pick a key whenever you walk over it.
• You cannot walk over a lock unless you have the corresponding key. For example, the key for the lock ‘A’ is ‘a’.
• There is exactly one key for each lock.

For Example:

You are given ‘GRID’= [[“@.aA”],[“.B#.”],[“...b”]]. Then the answer will be 5.

Ninja has to implement an ‘AVL_TREE’ from scratch.

He is given ‘N’ values, representing the values of nodes to be inserted. Ninja has to insert these values into the ‘AVL_TREE’ and return its root after inserting all the nodes.

Note: An ‘AVL_TREE’ is a self-balancing Binary Search Tree (BST) where the difference between heights of left and right subtrees cannot be more than one for all nodes.

For example:

There is a briefcase protected by a lock with 4 circular wheels. The password is a sequence of 4 digits.

1. Each wheel has 10 slots: ‘0’, ‘1’, ‘2’, ‘3’, ‘4’, ‘5’, ‘6’, ‘7’, ‘8’, ’9’.

2. The wheels can rotate freely and wrap around, ‘9’ can be left rotated to ‘8’ and right rotated to ‘0’, similarly ‘0’ can be right rotated to ‘1’ and left rotated to ‘9’. Rotation of one wheel counts to one rotation.

3. Initially, the lock starts at “0000”, a string representing the state of four wheels. 

You are given a list of dead ends (codes of 4 digits), meaning if at any point the lock displays any of these codes, the wheels of the lock will stop turning, and you will be unable to open it.

Given a target representing the code that will unlock the briefcase, return the minimum total number of turns required to open the lock, or -1 if it is not possible.

The discussion is basically on my previous work, mostly whatever  wrote in resume. 

How you solved this problem and approach?