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how to concatenate two dictionaries to create a new one in Python? [duplicate]
...nate the items and call dict on the resulting list:
$ python -mtimeit -s'd1={1:2,3:4}; d2={5:6,7:9}; d3={10:8,13:22}' \
'd4 = dict(d1.items() + d2.items() + d3.items())'
100000 loops, best of 3: 4.93 usec per loop
Fastest: exploit the dict constructor to the hilt, then one update:
$ python -mtim...
Why doesn't Java allow generic subclasses of Throwable?
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155
As mark said, the types are not reifiable, which is a problem in the following case:
try {
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Is there a difference between using a dict literal and a dict constructor?
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What is the difference between LL and LR parsing?
...back to some nonterminal by reversing a production.
As an example, an LR(1) parser (with one token of lookahead) might parse that same string as follows:
Workspace Input Action
---------------------------------------------------------
int + int + int Shift
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Undefined behavior and sequence points
... C++03
This answer is for the older versions of the C++ standard. The C++11 and C++14 versions of the standard do not formally contain 'sequence points'; operations are 'sequenced before' or 'unsequenced' or 'indeterminately sequenced' instead. The net effect is essentially the same, but the term...
Unix command to find lines common in two files
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error: default argument given for parameter 1
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Difference between CTE and SubQuery?
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103
In the sub-query vs simple (non-recursive) CTE versions, they are probably very similar. You w...
Get number days in a specified month using JavaScript? [duplicate]
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// Month here is 1-indexed (January is 1, February is 2, etc). This is
// because we're using 0 as the day so that it returns the last day
// of the last month, so you have to add 1 to the month number
// so it returns the correct amount of ...
