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Why do you have to call .items() when iterating over a dictionary in Python?
...te over the same items. Implementation-wise they are different operations (__contains__ vs. __iter__). But that little inconsistency would be somewhat confusing and, well, inconsistent.
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impr...
Why is reading lines from stdin much slower in C++ than Python?
...tl;dr: Because of different default settings in C++ requiring more system calls.
By default, cin is synchronized with stdio, which causes it to avoid any input buffering. If you add this to the top of your main, you should see much better performance:
std::ios_base::sync_with_stdio(false);
Normall...
What's the best way to iterate over two or more containers simultaneously
...wrote this wrapper around boost range: a function with one line of code is all I need. However, I would be interested if the performance of boost ranges is optimal as well.
– SebastianK
Nov 6 '14 at 15:45
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Oracle SQL: Update a table with data from another table
...
This is called a correlated update
UPDATE table1 t1
SET (name, desc) = (SELECT t2.name, t2.desc
FROM table2 t2
WHERE t1.id = t2.id)
WHERE EXISTS (
SELECT 1
FROM table2 t2...
Get local IP address in node.js
...
@CarterCole you need an extra call to .values() before flatten.
– Guido
Mar 4 '15 at 9:41
3
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How to access component methods from “outside” in ReactJS?
...
class Parent extends React.Class {
constructor(props) {
this._child = React.createRef();
}
componentDidMount() {
console.log(this._child.current.someMethod()); // Prints 'bar'
}
render() {
return (
<div>
<Child ref=...
UITableView is starting with an offset in iOS 7
...ed Aug 22 '13 at 19:05
Mick MacCallum
122k4040 gold badges273273 silver badges274274 bronze badges
answered Aug 22 '13 at 19:02
...
TypeError: Missing 1 required positional argument: 'self'
...p.getPumps()
Small example -
>>> class TestClass:
def __init__(self):
print("in init")
def testFunc(self):
print("in Test Func")
>>> testInstance = TestClass()
in init
>>> testInstance.testFunc()
in Test Func
...
Replace input type=file by an image
...
This works really well for me:
.image-upload>input {
display: none;
}
<div class="image-upload">
<label for="file-input">
<img src="https://icon-library.net/images/upload-photo-icon/upload-photo-icon-21...
Can an Option in a Select tag carry multiple values?
...
I was actually wondering this today, and I achieved it by using the php explode function, like this:
HTML Form (in a file I named 'doublevalue.php':
<form name="car_form" method="post" action="doublevalue_action.php">
...