Associate Software Engineer

You have been given three numbers ‘X’, ’Y’ and ‘Z’. You have to find the sum of all the numbers formed by the combination of the digits 3, 4 and 5. You can use 3 at most ‘X’ times, 4 at most ‘Y’ times, and 5 at most ‘Z’ times as a digit in numbers.

Note:

 Output the sum modulo 10 ^ 9 + 7.

For example :

If ‘X’ = 1, ‘Y’ = 1 and ‘Z’ = 0 then the output will be 84.

Explanation : 3 + 4 + 34 + 43 = 84

You are given a Weighted Directed Acyclic Graph (DAG) consisting of ‘N’ nodes and ‘E’ directed edges. Nodes are numbered from 0 to ’N’-1. You are also given a source node ‘Src’ in it. Your task is to find the longest distances from ‘Src’ to all the nodes in the given graph.

Return an array of ‘N’ integers where ‘ith’ integer gives the maximum distance of the node ‘i’ from the source node ‘Src’.

A Directed Acyclic Graph (DAG) is a directed graph that contains no cycles.

Note:

Print -1 if a node is not reachable from the given source node.

Example:

Consider the following DAG consists of 5 nodes and 7 edges,  Let the source node ‘Src’ be 0.

Then the maximum distance of node 0 from the source node 0 is 0. (the distance of a node from itself is always 0).
The maximum distance of node 1 from the source node 0 is 3. The path that gives this maximum distance is 0 -> 1.
The maximum distance of node 2 from the source node 0 is 10. The path that gives this maximum distance is 0 -> 2.
The maximum distance of node 3 from the source node 0 is 15. The path that gives this maximum distance is 0 -> 2 -> 3.
The maximum distance of node 4 from the source node 0 is 54. The path that gives this maximum distance is 0 -> 1 -> 4.

Thus we should print 0 3 10 15 54

You are given a positive integer N. Your task is to find the smallest number whose factorial contains at least N trailing zeroes.

Example :

Let N = 1. The smallest number whose factorial contains at least 1 trailing zeroes is 5 as 5! = 120.

Given a singly linked list of integers. Your task is to return the head of the reversed linked list.

For example:

The given linked list is 1 -> 2 -> 3 -> 4-> NULL. Then the reverse linked list is 4 -> 3 -> 2 -> 1 -> NULL and the head of the reversed linked list will be 4.

Follow Up :

Can you solve this problem in O(N) time and O(1) space complexity?

You have to implement the pop function of Max Priority Queue and implement using a heap.

Functions :

a) push(int x) : 'x' has to be inserted in the priority queue. This has been implemented already

b) pop() : return the maximum element in the priority queue, if priority queue is empty then return '-1'.

Example:

We perform the following operations on an empty priority queue:

When operation push(5) is performed, we insert 1 in the priority queue.

When operation push(2) is performed, we insert 2 in the priority queue. 

When operation pop() is performed, we remove the maximum element from the priority queue and print which is 5.

When operation push(3) is performed, we insert 1 in the priority queue.

When operation pop() is performed, we remove the maximum element from the priority queue and print which is 3.

You have been given a Binary Tree of 'N' nodes, where the nodes have integer values. Your task is to return the size of the largest subtree of the binary tree which is also a BST.

A binary search tree (BST) is a binary tree data structure which has the following properties.

• The left subtree of a node contains only nodes with data less than the node’s data.
• The right subtree of a node contains only nodes with data greater than the node’s data.
• Both the left and right subtrees must also be binary search trees.

Example:

Given binary tree:

In the given binary tree, subtree rooted at 2 is a BST and its size is 3.

Design Splitwise and change 3 features that you dont like about it.