大约有 11,400 项符合查询结果(耗时:0.0220秒) [XML]
Solving “Who owns the Zebra” programmatically?
...
Here's a solution in Python based on constraint-programming:
from constraint import AllDifferentConstraint, InSetConstraint, Problem
# variables
colors = "blue red green white yellow".split()
nationalities = "Norwegian German Dane Swede Engli...
What is compiler, linker, loader?
...king of compiler, linker and loader.
With reference to any language preferably c++.
14 Answers
...
Negative weights using Dijkstra's Algorithm
...rithm you have suggested will indeed find the shortest path in this graph, but not all graphs in general. For example, consider this graph:
Assume the edges are directed from left to right as in your example,
Your algorithm will work as follows:
First, you set d(A) to zero and the other dista...
sort object properties and JSON.stringify
My application has a large array of objects, which I stringify and save them to the disk. Unfortunately, when the objects in the array are manipulated, and sometimes replaced, the properties on the objects are listed in different orders (their creation order?). When I do JSON.stringify() on the arr...
u'\ufeff' in Python string
...
The Unicode character U+FEFF is the byte order mark, or BOM, and is used to tell the difference between big- and little-endian UTF-16 encoding. If you decode the web page using the right codec, Python will remove it for you. Examples:
#!python2
#coding: utf8...
Is there a performance gain in using single quotes vs double quotes in ruby?
Do you know if using double quotes instead of single quotes in ruby decreases performance in any meaningful way in ruby 1.8 and 1.9.
...
What is an abstract class in PHP?
What is an abstract class in PHP?
7 Answers
7
...
What is an initialization block?
We can put code in a constructor or a method or an initialization block. What is the use of initialization block? Is it necessary that every java program must have it?
...
NameError: name 'self' is not defined
...
Default argument values are evaluated at function define-time, but self is an argument only available at function call time. Thus arguments in the argument list cannot refer each other.
It's a common pattern to default an argument to None and add a test for that in code:
def p(self, b=...
Null coalescing in powershell
... you can use the standard Powershell if statements as an expression:
variable = if (condition) { expr1 } else { expr2 }
So to the replacements for your first C# expression of:
var s = myval ?? "new value";
becomes one of the following (depending on preference):
$s = if ($myval -eq $null) { "n...