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Accessing inactive union member and undefined behavior?
...s under the impression that accessing a union member other than the last one set is UB, but I can't seem to find a solid reference (other than answers claiming it's UB but without any support from the standard).
...
how to concatenate two dictionaries to create a new one in Python? [duplicate]
....93 usec per loop
Fastest: exploit the dict constructor to the hilt, then one update:
$ python -mtimeit -s'd1={1:2,3:4}; d2={5:6,7:9}; d3={10:8,13:22}' \
'd4 = dict(d1, **d2); d4.update(d3)'
1000000 loops, best of 3: 1.88 usec per loop
Middling: a loop of update calls on an initially-empty dict:...
What does if __name__ == “__main__”: do?
...variables are set up, the interpreter executes all the code in the module, one statement at a time. You may want to open another window on the side with the code sample so you can follow along with this explanation.
Always
It prints the string "before import" (without quotes).
It loads the math mo...
Regular expression to check if password is “8 characters including 1 uppercase letter, 1 special cha
...xpressions.
I think it would be easier to break your regex down and do it one bit at a time. It might take a bit more to do, but I am pretty sure that maintaining it and debugging it would be easier. This would also allow you to provide more directed error messages to your users (other than just In...
Asking the user for input until they give a valid response
...g and Custom Validation
Both of the above techniques can be combined into one loop.
while True:
try:
age = int(input("Please enter your age: "))
except ValueError:
print("Sorry, I didn't understand that.")
continue
if age < 0:
print("Sorry, your resp...
Combining Multiple Commits Into One Prior To Push
...em all once you're connected again. There's no reason to limit yourself to one commit per push.
I generally find that it's a good idea to keep each commit a single, logical, coherent change, that includes everything it needs to work (so, it does not leave your code in a broken state). If you have ...
jQuery click events firing multiple times
...
;) sorry. I spun my wheels around for a few days on this one too. I am still searching for a logical reason as to why it even happens in the first place.
– Rob
Feb 21 '13 at 4:11
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What is the difference between a map and a dictionary?
...
One is an older term for the other. Typically the term "dictionary" was used before the mathematical term "map" took hold. Also, dictionaries tend to have a key type of string, but that's not 100% true everywhere.
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Algorithm for creating a school timetable
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This problem is NP-Complete!
In a nutshell one needs to explore all possible combinations to find the list of acceptable solutions. Because of the variations in the circumstances in which the problem appears at various schools (for example: Are there constraints wit...
How to concatenate string variables in Bash
...lo World
In general to concatenate two variables you can just write them one after another:
a='Hello'
b='World'
c="${a} ${b}"
echo "${c}"
> Hello World
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