SDE - 1

You have been given an integer array/list(ARR) of size 'N'. It only contains 0s, 1s and 2s. Write a solution to sort this array/list.

Note :

Try to solve the problem in 'Single Scan'. ' Single Scan' refers to iterating over the array/list just once or to put it in other words, you will be visiting each element in the array/list just once.

You have been given a 2-D array 'mat' of size 'M x N' where 'M' and 'N' denote the number of rows and columns, respectively. The elements of each row are sorted in non-decreasing order.

Moreover, the first element of a row is greater than the last element of the previous row (if it exists).

You are given an integer ‘target’, and your task is to find if it exists in the given 'mat' or not.

Example:

Input: ‘M’ = 3, 'N' = 4, ‘mat’ = [[1, 2, 3, 4], [5, 6, 7, 8], [9, 10, 11, 12]], ‘target’ = 8

Output: true

Explanation: The output should be true as '8' exists in the matrix.

You are given an array 'a' of size 'n'.

Print the Next Greater Element(NGE) for every element.

The Next Greater Element for an element 'x' is the first element on the right side of 'x' in the array, which is greater than 'x'.

If no greater elements exist to the right of 'x', consider the next greater element as -1.

For example:

Input: 'a' = [7, 12, 1, 20]

Output: NGE = [12, 20, 20, -1]

Explanation: For the given array,

- The next greater element for 7 is 12.

- The next greater element for 12 is 20. 

- The next greater element for 1 is 20. 

- There is no greater element for 20 on the right side. So we consider NGE as -1.

You have been given a Singly Linked List of integers, determine if it forms a cycle or not. If there is a cycle, remove the cycle and return the list.

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

You are given an integer array 'ARR' of size 'N' and an integer 'S'. Your task is to return the list of all pairs of elements such that each sum of elements of each pair equals 'S'.

Note:

Each pair should be sorted i.e the first value should be less than or equals to the second value. 

Return the list of pairs sorted in non-decreasing order of their first value. In case if two pairs have the same first value, the pair with a smaller second value should come first.

You have been given a linked list of integers. Your task is to write a function that deletes a node from a given position, 'POS'.

Note :

Assume that the Indexing for the linked list always starts from 0.

If the position is greater than or equal to the length of the linked list, you should return the same linked list without any change.

Illustration :

The following images depict how the deletion has been performed.

Image-I :

Image-II :