多一份不为什么的坚持

摘要： 1.关系模型的三类完整性规则：实体完整性，参照完整性，用户定义的完整性规则。 1.1,数据库是指长期储存在计算机内，有组织的、可共享的大量数据的集合。数据库中的数据按照一定的数据模型组织、描述和存储， 较小的冗余度、具有较高的数据独立性和易扩展性，并可为各种用户专享。 1.2，数据库可以使用多种类型 阅读全文

摘要： Super Jumping! Jumping! Jumping! Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 32564 Accepted S 阅读全文

摘要： Max Sum Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 211310 Accepted Submission(s): 49611 Prob 阅读全文

摘要： A + B Problem Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 571020 Accepted Submission(s): 1811 阅读全文

摘要： A + B Problem II Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 310717 Accepted Submission(s): 6 阅读全文

摘要： Problem Description Many years ago , in Teddy’s hometown there was a man who was called “Bone Collector”. This man like to collect varies of bones , s 阅读全文

摘要： 问题描述： 有n阶楼梯，每次只能迈一步或两步，输出有多少种迈法到达楼顶。 解题心得： 递归方法：先考虑最后一步，可能是迈了一步，可能是迈了两步。所以step(n)=step(n-1)+step(n-2)，然后step(0)=1，step(1)=1; 但是递归方法时间复杂度太高，n=40就已经需要一段 阅读全文

摘要： 题目描述 Most of you have played card games (and if you haven’t, why not???) in which the deck of cards is randomized by shuffling it one or more times.A p 阅读全文

摘要： 题目描述 “What a boring world!”Julyed felt so bored that she began to write numbers on the coordinate paper. She wrote a “0” on the center, then wrote the 阅读全文

摘要： 题目描述 Jack and Jill developed a special encryption method, so they can enjoy conversations without worrrying about eavesdroppers. Here is how: let L be 阅读全文