文档介绍：The 4 th Collegiate Programming Contest of Central South University Problem Set Hosted by School of Information Science and Engineering April 25, 2010 This problem set contains 11 problems; pages are numbered from 1 to19. The 4 th Collegiate Programming Contest of Central South University 1 Problem A. Avatar Description In the Pandora, Jake found an old encryption algorithm. The plaintext, key and ciphertext are all four decimal numbers and all greater than 0. The way to get the ciphertext from the plaintext and the key is very simple: the ciphertext is the last four digits of the product of the plaintext and the key (for example: the plaintext is2010 and the key is4024, and then the product is8088240. So the ciphertext is 8240). Note that the plaintext and the key don ’t have leading 0, while the ciphertext might have. Now given the plaintext and the key, you are asked to figure out the ciphertext for Jake quickly. Input The first line is an integer T, which presents the number of test cases. Then there are T lines, each line has two integers, the first integer is the plaintext and the second is the key. Output For each test case, output the ciphertext. Sample Input 22010 4024 1234 1111 Sample Output 8240 0974 The 4 th Collegiate Programming Contest of Central South University 2 Problem B. Simple Line Editor Description puter used line editor, which allowed text tobe created and changed only within one line ata time. However, in line editor programs, typing, editing, and document display donot occur simultaneously (unlike the modern text editor like Microsoft Word). Typically, typing does not enter text directly into the document. Instead, users modify the document text by entering mands ona text-only terminal. Here is an example ofa simple line editor which can only process English. In addition, it has mands. ‘@’ and ‘#’.‘#’ means to cancel the previous letter, and ‘@’ mand which invalidates all the letters typed before. That is to say, if you want type “ aa”,but