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Why doesn't list have safe “get” method like dictionary?
...sociated with names) where it is inefficient to check if a key is present (and return its value) without throwing an exception, while it is super trivial to avoid exceptions accessing list elements (as the len method is very fast). The .get method allows you to query the value associated with a nam...
How to get distinct values from an array of objects in JavaScript?
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If this were PHP I'd build an array with the keys and take array_keys at the end, but JS has no such luxury. Instead, try this:
var flags = [], output = [], l = array.length, i;
for( i=0; i<l; i++) {
if( flags[array[i].age]) continue;
flags[array[i].age] = true;
...
What is an NP-complete in computer science?
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NP stands for Non-deterministic Polynomial time.
This means that the problem can be solved in Polynomial time using a Non-deterministic Turing machine (like a regular Turing machine but also including a non-deterministic "choice"...
UIActionSheet cancel button strange behaviour
...I can only activate it by clicking somewhere in the middle of the "Cancel" and "Ok" buttons.
7 Answers
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Number of elements in a javascript object
... implementations might keep track of such a value internally, there's no standard way to get it.
In the past, Mozilla's Javascript variant exposed the non-standard __count__, but it has been removed with version 1.8.5.
For cross-browser scripting you're stuck with explicitly iterating over the pro...
Python: access class property from string [duplicate]
I have a class like the following:
4 Answers
4
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vim 命令与快捷键 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...:set nu 设置行号插入命令i：光标后I：行首a:光标前A:行末o:光标后插入新行O:光标上插入新行定位h:leftj:downk:upl:right$:行尾0：行首H:...:set nu 设置行号
插入命令
i：光标后
I：行首
a:光标前
A:行末
o:光标后插入新行
O:光标上插入...
Linux C/C++进程单实例互斥代码分享 - C/C++ - 清泛网 - 专注C/C++及内核技术
Linux C/C++进程单实例互斥代码分享linux-process-singleton分享一段LinuxC C++程序只能启动一份实例的实现代码，原理是通过文件锁互斥实现，最重要的是考虑了不同用户运行同一程序互斥的场景，已经过充分的测试，可直接用于实际项...
Debian/Linux下安装OpenJDK8 - 操作系统(内核) - 清泛网 - 专注C/C++及内核技术
Debian/Linux下安装OpenJDK8linux_install_openjdk8因为Debian11的源里不再带OpenJDK8了，需要手工来安装。下载安装包因为手工安装，所以部分依赖包需要自己下载。wget http: snapshot debian org archive debian-security 202202 因为Debian11的源里不再带Open...
“Debug certificate expired” error in Eclipse Android plugins
I am using Eclipse Android plugins to build a project, but I am
getting this error in the console window:
17 Answers
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