SDE - 1

You are given an array 'arr' of length 'n', consisting of integers.

A subarray is a contiguous segment of an array. In other words, a subarray can be formed by removing 0 or more integers from the beginning and 0 or more integers from the end of an array.

Find the sum of the subarray (including empty subarray) having maximum sum among all subarrays.

The sum of an empty subarray is 0.

Example :

Input: 'arr' = [1, 2, 7, -4, 3, 2, -10, 9, 1]

Output: 11

Explanation: The subarray yielding the maximum sum is [1, 2, 7, -4, 3, 2].

You are given a non-empty binary tree where each node has a non-negative integer value. Return the maximum possible sum of path between any two leaves of the given tree.

The path is also inclusive of the leaf nodes and the maximum path sum may or may not go through the root of the given tree.

If there is only one leaf node in the tree, then return -1.

You are given an undirected graph as an adjacency matrix consisting of 'v' vertices and an integer 'm'.

You need to return 'YES' if you can color the graph using at most 'm' colors so that no two adjacent vertices are the same. Else, return 'NO'.

For example:

Input:
If the given adjacency matrix is:
[0 1 0]
[1 0 1]
[0 1 0] and 'm' = 3.

Output: YES

Explanation:
The given adjacency matrix tells us that 1 is connected to 2 and 2 is connected to 3. We can use three different colors and color all three nodes.
Hence we return true.

Given an array/list of integer numbers 'CHOCOLATES' of size 'N', where each value of the array/list represents the number of chocolates in the packet. There are ‘M’ number of students and the task is to distribute the chocolate to their students. Distribute chocolate in such a way that:

1. Each student gets at least one packet of chocolate.

2. The difference between the maximum number of chocolate in a packet and the minimum number of chocolate in a packet given to the students is minimum.

Example :

Given 'N' : 5 (number of packets) and 'M' : 3 (number of students)

And chocolates in each packet is : {8, 11, 7, 15, 2}

All possible way to distribute 5 packets of chocolates among 3 students are -

( 8,15, 7 ) difference of maximum-minimum is ‘15 - 7’ = ‘8’
( 8, 15, 2 ) difference of maximum-minimum is ‘15 - 2’ = ‘13’ 
( 8, 15, 11 ) difference of maximum-minimum is ‘15 - 8’ = ‘7’
( 8, 7, 2 ) difference of maximum-minimum is ‘8 - 2’ = ‘6’
( 8, 7, 11 ) difference of maximum-minimum is ‘11 - 7’ = ‘4’
( 8, 2, 11 ) difference of maximum-minimum is ‘11 - 2’ = ‘9’
( 15, 7, 2 ) difference of maximum-minimum is ‘15 - 2’ = 13’
( 15, 7, 11 ) difference of maximum-minimum is ‘15 - 7’ = ‘8’
( 15, 2, 11 ) difference of maximum-minimum is ‘15 - 2’ = ‘13’
( 7, 2, 11 ) difference of maximum-minimum is ‘11 - 2’ = ‘9’

Hence there are 10 possible ways to distribute ‘5’ packets of chocolate among the ‘3’ students and difference of combination (8, 7, 11) is ‘maximum - minimum’ = ‘11 - 7’ = ‘4’ is minimum in all of the above.

You have been given a string ‘A’ consisting of lower case English letters. Your task is to find the length of the longest palindromic subsequence in ‘A’.

A subsequence is a sequence generated from a string after deleting some or no characters of the string without changing the order of the remaining string characters. (i.e. “ace” is a subsequence of “abcde” while “aec” is not).

A string is said to be palindrome if the reverse of the string is the same as the actual string. For example, “abba” is a palindrome, but “abbc” is not a palindrome.