In this problem, a dictionary is collection of key-value pairs, where keys are lower-case letters, and values are non-negative integers. Given an old dictionary and a new dictionary, find out what were changed.

Each dictionary is formatting as foll >>继续阅读

The word “search engine” may not be strange to you. Generally speaking, a search engine searches the web pages available in the Internet, extracts and organizes the information and responds to users’ queries with the most relevant pages. World famous >>继续阅读

I mean your borrowers of books — those mutilators of collections, spoilers of the symmetry of shelves, and creators of odd volumes. – (Charles Lamb, Essays of Elia (1823) ‘The Two Races of Men’)

Like Mr. Lamb, librarians have their problems with bo >>继续阅读

For an electronic mail application you are to describe the SMTP-based communication that takes place between pairs of MTAs. The sender’s User Agent gives a formatted message to the sending Message Transfer Agent (MTA). The sending MTA communicates wi >>继续阅读

Peter studies the theory of relational databases. Table in the relational database consists of values that are arranged in rows and columns.

There are different normal forms that database may adhere to. Normal forms are designed to minimize the red >>继续阅读

The computer company you work for is introducing a brand new computer line and is developing a new Unix-like operating system to be introduced along with the new computer. Your assignment is to write the formatter for the ls function.

Your program >>继续阅读

Most crossword puzzle fans are used to anagrams — groups of words with the same letters in different orders — for example OPTS, SPOT, STOP, POTS and POST. Some words however do not have this attribute, no matter how you rearrange their letters, you c >>继续阅读

Andy, 8, has a dream - he wants to produce his very own dictionary. This is not an easy task for him, as the number of words that he knows is, well, not quite enough. Instead of thinking up all the words himself, he has a briliant idea. From his book >>继续阅读

In Hangman Judge,'' you are to write a program that judges a series of Hangman games. For each game, the answer to the puzzle is given as well as the guesses. Rules are the same as the classic game of hangman, and are given as follows:

The conte >>继续阅读

You have devised a new encryption technique which encodes a message by inserting between its characters randomly generated strings in a clever way. Because of pending patent issues we will not discuss in detail how the strings are generated and inser >>继续阅读

An organic compound is any member of a large class of chemical compounds whose molecules contain carbon. The molar mass of an organic compound is the mass of one mole of the organic compound. The molar mass of an organic compound can be computed from >>继续阅读

There is an objective test result such as “OOXXOXXOOO”. An ‘O’ means a correct answer of a problem and an ‘X’ means a wrong answer. The score of each problem of this test is calculated by itself and its just previous consecutive ‘O’s only when the an >>继续阅读

A common typing error is to place the hands on the keyboard one row to the right of the correct position. So ‘Q’ is typed as ‘W’ and ‘J’ is typed as ‘K’ and so on. You are to decode a message typed in this manner.

Input

Input consists of several >>继续阅读

IP Address

Suppose you are reading byte streams from any device, representing IP addresses. Your task is to convert a 32 characters long sequence of '1s' and '0s' (bits) to a dotted decimal format. A dotted decimal format for an IP address is form >>继续阅读

Substrings

Problem Description

You are given a number of case-sensitive strings of alphabetic characters, >>继续阅读

You are working in a team that writes Incredibly Customizable Programming Codewriter (ICPC) which is basically a text editor with bells and whistles. You are working on a module that takes a piece of code containing some definitions or other tabular >>继续阅读