# Tag Archives: DFS

## Print all n digit patterns formed by mobile KeypadNovember 12, 2017

Given a number n. we need to print all N digit pattern formed by mobile Keypad. Note: we can move up, down, left, right from… Read More »

## Count all 0s which are blocked by 1s in binary matrixNovember 6, 2017

Given Binary matrix. Task is count all zeros which are surrounded by one (may not be immediate neighbor). Note: here we are only taking four… Read More »

## Number of groups formed in a graph of friendsOctober 22, 2017

Given n friends and their friendship relations, find the total number of groups that exist. And the number of ways of new groups that can… Read More »

## Maximum number of edges to be added to a tree so that it stays a Bipartite graphSeptember 21, 2017

A tree is always a Bipartite Graph as we can always break into two disjoint sets with alternate levels. In other words we always color… Read More »

## Make all combinations of size kAugust 23, 2017

Given two numbers n and k and you have to find all possible combination of k numbers from 1…n. Examples: Input : n = 4… Read More »

## Diameter of a tree using DFSAugust 22, 2017

The diameter of a tree (sometimes called the width) is the number of nodes on the longest path between two leaves in the tree. The… Read More »

## Calculate number of nodes in all subtrees | Using DFSAugust 10, 2017

Given a tree in form of adjacency list we have to calculate the number of nodes in the subtree of each node, while calculating the… Read More »

## Alphanumeric Abbreviations of a StringJuly 23, 2017

Given a string of characters of length less than 10. We need to print all the alpha-numeric abbreviation of the string. The alpha-numeric abbreviation is… Read More »

## Clone a Directed Acyclic GraphJune 25, 2017

A directed acyclic graph (DAG) is a graph which doesn’t contain a cycle and has directed edges. We are given a DAG, we need to… Read More »

## Minimum edge reversals to make a rootJune 2, 2017

Given a directed tree with V vertices and V-1 edges, we need to choose such a root (from given nodes from where we can reach… Read More »

## Move weighting scale alternate under given constraintsMay 10, 2017

Given a weighting scale and an array of different positive weights where we have an infinite supply of each weight. Our task is to put… Read More »

## Top 10 Interview Questions on Depth First Search (DFS)May 1, 2017

Depth-first search (DFS) is an algorithm for traversing or searching tree or graph data structures. One starts at the root (selecting some arbitrary node as… Read More »

## Number of pair of positions in matrix which are not accessibleMarch 31, 2017

Given a positive integer N. Consider a matrix of N X N. No cell can be accessible from any other cell, except the given pair… Read More »

## Maximum product of two non-intersecting paths in a treeMarch 23, 2017

Given an undirected connected tree with N nodes (and N-1 edges), we need to find two paths in this tree such that they are non-intersecting… Read More »

## Maximum edge removal from tree to make even forestMarch 20, 2017

Given an undirected tree which has even number of vertices, we need to remove the maximum number of edges from this tree such that each… Read More »