Article CTS Interview Questions

The company was started in 1994, as an in-house IT services unit of the Dun & Bradstreet Corporation (D&B) and its operating units. Initially a joint venture between Dun & Bradstreet (76%) and Satyam Computer Services Ltd. (24%), it soon became a 100% subsidiary of D&B Corp. In 1996, the company became a division of the Cognizant Corporation, after the split-up of Dun & Bradstreet Corporation.

In June 1998, Cognizant Corporation was again split into independent companies, and Cognizant Technology Solutions was formed as a division of IMS Health, a provider of information solutions to the pharmaceutical and healthcare industries. The same year, the company completed its initial public offering and was listed on the NASDAQ. In November 2002, IMS Health divested its majority interest in Cognizant through a tax-free split-off.

In its early years, Cognizant's clientele primarily comprised the sister companies in the Dun and Bradstreet group of companies and the services were focused on Y2K compliance, Application Support and Maintenance (predominantly in client server and mainframe applications).

Cognizant has aligned its businesses vertically and has clients in

• Banking & Financial Services
• Consumer Goods
• Healthcare
• Travel & Hospitality
• Information, Media & Entertainment
• Insurance
• Life Sciences
• Retail

1. What is a candidate key?
Solution:
In the relational model of databases, a candidate key of a relation is a minimal superkey for that relation; that is, a set of attributes such that

• the relation does not have two distinct tuples with the same values for these attributes
• there is no proper subset of these attributes for which the 1st statement holds.

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2. Write a "Hello World" program in C without using a semicolon #include <stdio.h> main(){ if (!printf("Hello World")){} }

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3. What is the difference between a B-Tree and a Binary search tree?

B-Tree:
In computer science, a B-tree is a tree data structure that keeps data sorted and allows searches, insertions, deletions, and sequential access in logarithmic amortized time. The B-tree is a generalization of a binary search tree in that more than two paths diverge from a single node. Unlike self-balancing binary search trees, the B-tree is optimized for systems that read and write large blocks of data. It is most commonly used in databases and filesystems.
Binary Search Tree
In computer science, a binary search tree (BST) is a node based binary tree data structure which has the following properties

• The left subtree of a node contains only nodes with keys less than the node's key.
• The right subtree of a node contains only nodes with keys greater than the node's key.
• Both the left and right subtrees must also be binary search trees.