SDE - 1

You are given an array of N integers and an integer K. For each array element, you are allowed to increase or decrease it by a value k. The task is to minimize the difference between the maximum element and the minimum element after modifications.

You are given the arrival and departure times of N trains at a railway station in a day. You need to find the minimum of platforms required for the railway station such that no train waits i.e No train should wait for the platform to be clear or free.

There is a country with 'N' cities and 'M' bidirectional roads of 3 types.

Type 1: Two Wheeler Road, It means only vehicles having two wheels can use this road.
Type 2: Four Wheeler Road, It means only vehicles having four wheels can use this road.
Type 3: Both two and four Wheeler Road, It means this road can be used by both type of vehicles.

The problem is to find the maximum number of roads that can be removed such that a path exists for every pair of cities for each two-wheeler and four-wheeler vehicle.

Note:

1. Roads may form a cycle.

2. The cities do not have multiple same roads i.e all the roads are unique.

3. If every city cannot be reached, then return -1.

An archer is hitting the target(a circle). He fires the first shot and then the second shot. Given that his  shot was better than the second. Find the probability that the third shot that he fires is best among the three. The three shots are independent of each other.

You have been given a Binary Tree of integers, find the minimum depth of this Binary Tree. The minimum depth of a Binary Tree is the number of nodes along the shortest path from the root node down to the nearest leaf node.

Note:

A leaf is a node with no children.

For example:

For the given binary tree

Output: 2
The shortest path is from root node 1 to leaf node 2 which contains 2 nodes in the path. Hence, the minimum depth is 2.

A ninja needs to complete ‘n’ tasks. Each task is represented by an uppercase letter of the English alphabet. Different letters are assigned to different tasks. A ninja can complete tasks in any order. He takes one unit of time to complete one task. For each unit of time, he could complete either one task or just be idle.

Ninja easily gets bored by doing the same task again. So he decided to keep at least ‘t’ units of time between any two same tasks.

You are given a string ‘tasks’ consisting of ‘n’ uppercase letters of the English alphabet, representing the tasks ninja need to complete, and an integer ‘t’ representing the least units of time between any two same tasks. Find out the minimum total units of time ninja will take to complete all ‘n’ tasks.