# Category Archives: Mathematical

GCD (Greatest Common Divisor) or HCF (Highest Common Factor) of two numbers is the largest number that divides both of them.  For example, GCD ofâ€¦ Read More
Given two matrices, the task is to multiply them. Matrices can either be square or rectangular: Examples:  (Square Matrix Multiplication) Input: mat1[m][n] = { {1,â€¦ Read More
Given an integer n, write a function that returns count of trailing zeroes in n!. Examples :  Input: n = 5 Output: 1 Factorial of 5â€¦ Read More
Catalan numbers are defined as a mathematical sequence that consists of positive integers, which can be used to find the number of possibilities of variousâ€¦ Read More
Given a keypad as shown in the diagram, and an n digit number, list all words which are possible by pressing these numbers. Before theâ€¦ Read More
Online Coding Round: Find if a given string contains duplicates Given a BST, find the maximum N elements of the tree Given a BST, convertâ€¦ Read More
Given an array arr[] of size n where every element is in the range from 0 to n-1. Rearrange the given array so that arr[i]â€¦ Read More
Given two rectangles, find if the given two rectangles overlap or not.Note that a rectangle can be represented by two coordinates, top left and bottomâ€¦ Read More
Given two numbers, write a C program to swap the given numbers. Input : x = 10, y = 20; Output : x = 20,â€¦ Read More
Given two variables, x, and y, swap two variables without using a third variable.  Method 1 (Using Arithmetic Operators)  The idea is to getâ€¦ Read More
Given an array of integers, find sum of its elements.Examples :  Input : arr[] = {1, 2, 3}Output : 6Explanation: 1 + 2 + 3â€¦ Read More
The problem is to count all the possible paths from the top left to the bottom right of a M X N matrix with theâ€¦ Read More
Given a positive integer n, generate all possible unique ways to represent n as sum of positive integers.  Examples:  Input: n = 2 Output: 2â€¦ Read More
Given two integers, write a function to multiply them without using multiplication operator.There are many other ways to multiply two numbers (For example, see this).â€¦ Read More
Online Test on InterviewStreet: 18 MCQs (Normal C loop questions, networking, dbms, os, analytical) 2 Coding questions 1. Check if an undirected graph is a tree or not. 2.â€¦ Read More