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New Array from Index Range Swift
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183
This works for me:
var test = [1, 2, 3]
var n = 2
var test2 = test[0..<n]
Your issue could...
Efficient way to rotate a list in python
...method.
from collections import deque
items = deque([1, 2])
items.append(3) # deque == [1, 2, 3]
items.rotate(1) # The deque is now: [3, 1, 2]
items.rotate(-1) # Returns deque to original state: [1, 2, 3]
item = items.popleft() # deque == [2, 3]
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How to create abstract properties in python abstract classes
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3 Answers
3
Active
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Reverse Range in Swift
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Update For latest Swift 3 (still works in Swift 4)
You can use the reversed() method on a range
for i in (1...5).reversed() { print(i) } // 5 4 3 2 1
Or stride(from:through:by:) method
for i in stride(from:5,through:1,by:-1) { print(i) } // 5 4...
typedef fixed length array
I have to define a 24-bit data type.I am using char[3] to represent the type. Can I typedef char[3] to type24 ? I tried it in a code sample. I put typedef char[3] type24; in my header file. The compiler did not complain about it. But when I defined a function void foo(type24 val) {} in my C...
How to print number with commas as thousands separators?
... commas as thousands separators. For example, I want to show the number 1234567 as 1,234,567 . How would I go about doing this? I have seen many examples on Google, but I am looking for the simplest practical way.
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Why is address zero used for the null pointer?
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edited May 3 '10 at 17:44
answered May 3 '10 at 17:22
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List comprehension vs map
...:
$ python -mtimeit -s'xs=range(10)' 'map(hex, xs)'
100000 loops, best of 3: 4.86 usec per loop
$ python -mtimeit -s'xs=range(10)' '[hex(x) for x in xs]'
100000 loops, best of 3: 5.58 usec per loop
An example of how performance comparison gets completely reversed when map needs a lambda:
$ pytho...
Return multiple values in JavaScript?
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1380
No, but you could return an array containing your values:
function getValues() {
return [...
rails 3 validation on uniqueness on multiple attributes
I use Rails 3.0.0.beta4
3 Answers
3
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