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How do you check in python whether a string contains only numbers?
...u'll want to use the isdigit method on your str object:
if len(isbn) == 10 and isbn.isdigit():
From the isdigit documentation:
str.isdigit()
Return True if all characters in the string are digits and there is at least one character, False otherwise. Digits include decimal characters and digits tha...
Executors.newCachedThreadPool() versus Executors.newFixedThreadPool()
...
I think the docs explain the difference and usage of these two functions pretty well:
newFixedThreadPool
Creates a thread pool that reuses a
fixed number of threads operating off
a shared unbounded queue. At any
point, at most nThreads threads will
be...
how to listen to N channels? (dynamic select statement)
...cks until at least one of the cases can
proceed, makes a uniform pseudo-random choice, and then executes that
case. It returns the index of the chosen case and, if that case was a
receive operation, the value received and a boolean indicating whether
the value corresponds to a send on the ch...
C state-machine design [closed]
I am crafting a small project in mixed C and C++. I am building one small-ish state-machine at the heart of one of my worker thread.
...
When vectors are allocated, do they use memory on the heap or the stack?
... store.
vector<Type*> vect;
will allocate the vector on the stack and a bunch of pointers on the free store, but where these point is determined by how you use them (you could point element 0 to the free store and element 1 to the stack, say).
...
How to create Temp table with SELECT * INTO tempTable FROM CTE Query
...T, EventTitle
,EventType from Calendar
where (PlannedDate >= GETDATE()) AND ',' + EventEnumDays + ',' like '%,' + cast(datepart(dw, PlannedDate) as char(1)) + ',%'
or EventEnumDays is null
Make sure that the table is deleted after use
If(OBJECT_ID('tempdb..#temp') Is Not Null)
Begin
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How to set OnClickListener on a RadioButton in Android?
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I'd think a better way is to use RadioGroup and set the listener on this to change and update the View accordingly (saves you having 2 or 3 or 4 etc listeners).
RadioGroup radioGroup = (RadioGroup) findViewById(R.id.yourRadioGroup);
radioGroup.setOnChe...
BrightnessTools 拓展：设置手机亮度的工具 · App Inventor 2 中文网
...最大亮度，则返回 255。
注意：Android 系统规定最大值应为 255。
但是，不同品牌的手机设置不同，例如部分小米手机的最大值是 4000。
注册 Changed 的...
What are copy elision and return value optimization?
...to a copy or move constructor is elided, that constructor must still exist and must be accessible. This ensures that copy elision does not allow copying objects which are not normally copyable, e.g. because they have a private or deleted copy/move constructor.
C++17: As of C++17, Copy Elision is gua...
Can a pointer to base point to an array of derived objects?
I went to a job interview today and was given this interesting question.
3 Answers
3
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