peek operation in stack using javascript

To check the topmost element unfortunately you must explicitly index it var top = stack[stack.length-1]; the syntax stack[-1] (that would work in Python) doesn’t work: negative indexes are valid only as parameters to slice call. // The same as stack[stack.length-1], just slower and NOT idiomatic var top = stack.slice(-1)[0]; To extract an element there is …

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Escape analysis in Java

With this version of java -XX:+DoEscapeAnalysis results in far less gc activity and 14x faster execution. $ java -version java version “1.6.0_14” Java(TM) SE Runtime Environment (build 1.6.0_14-b08) Java HotSpot(TM) Client VM (build 14.0-b16, mixed mode, sharing) $ uname -a Linux xxx 2.6.18-4-686 #1 SMP Mon Mar 26 17:17:36 UTC 2007 i686 GNU/Linux Without escape …

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C++: Stack’s push() vs emplace() [duplicate]

To fully understand what emplace_back does, one must first understand variadic templates and rvalue references. This is a fairly advanced, and deep concept in modern C++. On a map, it would be labeled “there be dragons”. You say that you’re new to C++ and trying to learn this stuff. This may not be the answer …

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Parenthesis/Brackets Matching using Stack algorithm

Your code has some confusion in its handling of the ‘{‘ and ‘}’ characters. It should be entirely parallel to how you handle ‘(‘ and ‘)’. This code, modified slightly from yours, seems to work properly: public static boolean isParenthesisMatch(String str) { if (str.charAt(0) == ‘{‘) return false; Stack<Character> stack = new Stack<Character>(); char c; …

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Java Stack push() vs add()

Kalyanaraman Santhanam: Edit: Will I encounter any issues if I use add(…) instead of push(…)? Definitly, you will not encounter any issues, because add is part of List interface as well as the Stack, but you should to notice the further readability of your code and your intentions in it by other programmers. push method …

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