Find all subsets of size K from a given number N (1 to N)

Objective: Given two integers N and K, Write an algorithm to find subsets of size K from the numbers 1 to N.  Example: N = 5 K = 3 Output: [1, 2, 3] [1, 2, 4] [1, 2, 5] [1, 3, 4] [1, 3, 5] [1, 4, 5] [2, 3, 4] [2, 3, 5] [2, … Read more Find all subsets of size K from a given number N (1 to N)

Find all possible combinations with sum K from a given number N(1 to N) with the repetition of numbers is allowed

Objective: Given two integers N and K, Write an algorithm to find possible combinations that add to K, from the numbers 1 to N.  Condition: An integer from 1 to N can be repeated any number of times in combination. Example: N = 5 K = 3 Output: [1, 1, 1] [1, 2] [3] N … Read more Find all possible combinations with sum K from a given number N(1 to N) with the repetition of numbers is allowed

Stable Marriage Problem – Gale–Shapley Algorithm – Java

Stable Marriage Given N men and N women and the marriage preference order for each man and woman. Their marriage will be stable when these men and women marry in such a manner so that everyone gets the most desired partner as per the availability( partners in a marriage cannot find anyone else better than … Read more Stable Marriage Problem – Gale–Shapley Algorithm – Java

Construct the largest number from the given array.

Objective: Given an array of integers, write an algorithm to construct the largest number possible by appending the array elements.  Example: Given Input: [7, 78] Largest Number Possible: 787 Explanation: two possibilities are 778 and 787. 787 is larger than 778. Given Input: [25, 42, 39] Largest Number Possible: 423925 Approach:  Normal sorting in descending … Read more Construct the largest number from the given array.

Given an array, find three-element sum closest to Zero

Objective: Given an array of integers, find the sum of any three elements which is closest to zero. The array may contain positive and negative elements.  Example:  Given Input: [-1, 4, -2, 5, 10, -5] Minimum Sum with three elements is: 1 Explanation:  -1, 4, -2 sums to -1  Given Input: [-1, 4, -2, 5, … Read more Given an array, find three-element sum closest to Zero

Given an array, print all unique subsets with a given sum.

Objective: Given an array of integers and number N, Write an algorithm to find and print all the subsets of the array for which sum is equal to N. Example: input [] = {6,2,7,8,2,4,1,3,7,5} Sum = 8 Output: [1, 2, 2, 3] [1, 2, 5] [1, 3, 4] [1, 7] [2, 2, 4] [2, 6] … Read more Given an array, print all unique subsets with a given sum.

Sum of length of subsets which contains given value K and all elements in subsets are less than equal to K.

Objective: Given an array of numbers and integer K. Your task is to find lengths of all the subsets which contain value K and all elements in the subset are less than equal to K. Example: Given Input: [1, 5, 2, 3, 8, 6, 2, 4, 9, 5, 2], and K = 5 Length of … Read more Sum of length of subsets which contains given value K and all elements in subsets are less than equal to K.

Find all unique combinations of numbers (from 1 to 9 ) with sum to N

Objective: Given an integer N, Write an algorithm to select numbers from 1 to 9 and make combinations such that its sum to N.  Example: N= 5 Output:  [1, 4] [2, 3] [5] N =12 [1, 2, 3, 6] [1, 2, 4, 5] [1, 2, 9] [1, 3, 8] [1, 4, 7] [1, 5, 6] … Read more Find all unique combinations of numbers (from 1 to 9 ) with sum to N

Number of Intervals in which given value lies

Objective: Given a list of intervals with start and end for each interval. You have given a value V, write an algorithm to find the number of intervals in which the value V lies.  Example: Given Interval: [[1,7], [3,10], [12,15]] Value : 6 lies in Intervals: 2 Given Interval: [[1,7], [3,10], [12,15]] Value : 11 … Read more Number of Intervals in which given value lies

Unique Integers in array that sum up to zero.

Objective: Given an integer N, write a function to return an array containing N unique integers that sum up to zero. There are many possible arrays that sum up to 0 for any N, you need to return any one of such arrays. Example: N = 4 Output: [-1, 1, -2, 2] or [-1, -2, … Read more Unique Integers in array that sum up to zero.

Articulation Points OR Cut Vertices in a Graph

Objective: Given a graph, write an algorithm to find all the articulation points or cut vertices. Articulation Points: In a graph, a vertex is called an articulation point if removal of that vertex (along with all the edges associated with that vertex) increases the number of connected components or in other words, removal of that … Read more Articulation Points OR Cut Vertices in a Graph

Check If Given Undirected Graph is a tree

Objective: Given an undirected graph, Write an algorithm to determine whether its tree or not. An undirected graph is a tree if it has properties mentioned below There is no cycle present in the graph. The graph is connected. (All the vertices in the graph are connected) Example: Recommended articles to read before continue reading … Read more Check If Given Undirected Graph is a tree

Find the number of distinct Islands OR connected components.

Objective: Given a 2d grid map of ‘1’s (land) and ‘0’s (water), count the number of distinct or unique islands. Island: An island is surrounded by water and is formed by connecting adjacent lands horizontally or vertically. Assume all four edges of the grid are all surrounded by water. Given such a grid, write an … Read more Find the number of distinct Islands OR connected components.

Check the completeness of given binary tree | Set 2 – Using Level Order Traversal

Objective: Given a binary tree, write an algorithm to determine whether the tree is complete or not using Level order traversal. Earlier we had solved this problem by counting the number of nodes in the tree. (Read – Check the completeness of given binary tree | Set 1 – Using Node Count. In this article, … Read more Check the completeness of given binary tree | Set 2 – Using Level Order Traversal

Print All Paths in Dijkstra’s Shortest Path Algorithm

Objective:  Given a graph and a source vertex write an algorithm to find the shortest path from the source vertex to all the vertices and print the paths all well. Example: We strongly recommend reading the following before continuing to read Graph Representation – Adjacency List Dijkstra’s shortest path algorithm – Priority Queue method We will … Read more Print All Paths in Dijkstra’s Shortest Path Algorithm