摘要： equals vs == equals : always remember to override hashCode if you override equals so as not to "break the contract". if equals. the hashCode must be same.== : it returns true if both variables refer to the same object, if their references are one and the same.why in the abstract class, can 阅读全文

摘要： Thread safety A piece of code is thread-safe if it only manipulates shared data structures in a manner that guarantees safe execution by multiple threads at the same time. #include int increment_counter (){ static int counter = 0; static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZ... 阅读全文

摘要： rope (data structure) + KMP(string search) O(m+n) 阅读全文

摘要： 局部内部类为什么只能访问final局部变量？分类：Java2012-01-07 14:03874人阅读评论(1)收藏举报stringthreadclassjava[html]view plaincopy//只有定义成finalStringobj才不会报错publicvoidtest(finalStringobj){ThreadmyThread=newThread(){publicvoidrun(){System.out.println(obj);}};myThread.start();}[html]view plaincopypublicclassOuterClass{publicvoidou 阅读全文

摘要： In an white paper titled “Java: an Overview” byJames Gosling in February 1995 gives an idea on why multiple inheritance is not supported in Java.JAVA omits many rarely used, poorly understood, confusing features of C++ thatin our experience bring more grief than benefit. This primarily consists ofope 阅读全文

摘要： 羅馬數字(Roman Numbers)羅馬字數字羅馬字數字羅馬字數字羅馬字數字I1XI11XXI21C100II2XII12XXIX29CI101III3XIII13XXX30CC200IV4XIV14XL40D500V5XV15XLVIII48DC600VI6XVI16IL49CM900VII7XVII17L50M1000VIII8XVIII18LX60MDCLXVI1666IX9XIX19XC90MCMLXX1970X10XX20XCVIII98 阅读全文

摘要： import java.util.ArrayList;import java.util.LinkedList;import java.util.List;import java.util.Queue;import java.util.Stack;enum Dirction {left , right} public class Tree { private BinaryTreeNode root; private List list = new ArrayList(); Dirction current = Dirction.right; ... 阅读全文

摘要： Given a node from a cyclic linked list which has been sorted, write a function to insert a value into the list such that it remains a cyclic sorted li... 阅读全文

摘要： 1. for i:=1 to n do swap(a[i], a[random(1,n)]); // 凑合，但不是真正随机2. for i:=1 to n do swap(a[i], a[random(i,n)]); // 真正的随机算法其中，random(a,b)函数用于返回一个从a到b（包括a和b）的随机整数。2）的时间复杂度O（n）， 空间复杂度O(1); 阅读全文

摘要： Maximum Depth of Binary TreeMaximum Depth of Binary TreeGiven a binary tree, find its maximum depth.The maximum depth is the number of nodes along the longest path from the root node down to the farthest leaf node.Solution - RecursionThe recursion algorithm is easy to come up:Perform a DFS (depth-fi 阅读全文