My software development journey
Given an array of size N and a number K. We have to find the sub-array of size K such that the sum of it’s elements is minimum among all K-size sub arrays. For example Let us consider the following array of size 10. {1, 2, 1, 3, 1, 1, 1, 4, 2, 3} The…
Given an array containing all elements twice except two numbers. Write a program to find those two numbers. For example let us consider the following array {2, 3, 2, 1, 4, 1, 4, 5} The answer is {3,5} because they appear only once and all remaining elements appear twice. This question is somewhat similar to earlier…
Given two numbers, calculate the number of bits required to change from one number to the other. For example 12 in binary can be represented as 1100. 15 is represented as 1111. We need to change two bits to convert one number from the other as the last two bits are different. We can find…
Given a singly linked list, we have to swap the adjacent nodes in it. For example some input/output samples are given below Input output ————————————————- 1->2->3->4->X 2->1->4->3->X 1->2->3->4->5->X …
How do we write a program to find the prime factorization of a given number? For example prime factorization for 18 can written as 2 * 3 * 3 or 2 * 3 ^ 2. For any number there is only one possible prime factorization. An efficient algorithm can be given as follows. we run…
Given a number, how do we write a program to find all of it’s factors or divisors. For example, for the number 18, the factors are {1, 2, 3, 6, 9, 18}. An immediate algorithm that comes to our mind is to run a loop from 1 to n. In each iteration check if the…
In this post we talk a little bit about the constant pointers and pointer to a constant and the difference between them. In C programming, pointer is a crucial concept and it is always good to have a clear understanding of the fundamentals. Constant pointers: Constant pointer as the name indicates is a pointer whose…
Given a singly linked list, how do we reverse it by re-arranging the links? For example if the given linked list is 1 -> 2 -> 3 -> NULL. The output of reverse method should be 3 -> 2 -> 1 -> NULL. The following diagram shows the simple steps to perform the reversal. And…
Given a two dimensional array or a matrix, how do we write a program to print the elements in a spiral order. For example the spiral order for the following matrix is 1 2 3 4 8 12 16 15 14 13 9 5 6 7 11 10 1 2 3 4…
Given a doubly linked list, how do we reverse it by just re-arranging the pointers? Here is an example of input/output. The following picture depicts how we re-arrange the pointers. Here is the Java implementation.