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How do I sort one vector based on values of another
I have a vector x, that I would like to sort based on the order of values in vector y. The two vectors are not of the same length.
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What is the optimal algorithm for the game 2048?
...ructures in which adjacent tiles are decreasing in value, but of course in order to merge, adjacent tiles need to be the same value. Therefore, the smoothness heuristic just measures the value difference between neighboring tiles, trying to minimize this count.
A commenter on Hacker News gave an int...
What is your most productive shortcut with Vim?
...d of your file as a scratch space). This will have preserved the relative order of all the "foo" lines while having extracted them from the rest of the list. (This would be equivalent to doing something like: 1G!GGmap!Ggrep foo<ENTER>1G:1,'a g/foo'/d (copy the file to its own tail, filter th...
What are the differences between ArrayList and Vector?
...rrayList and Vector both implements List interface and maintains insertion order.But there are many differences between ArrayList and Vector classes...
ArrayList -
ArrayList is not synchronized.
ArrayList increments 50% of current array size if number of element exceeds from its capacity.
ArrayLi...
What belongs in an educational tool to demonstrate the unwarranted assumptions people make in C/C++?
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The order of evaluation of subexpressions, including
the arguments of a function call and
operands of operators (e.g., +, -, =, * , /), with the exception of:
the binary logical operators (&& and ||),
the ternary con...
How can I extract embedded fonts from a PDF as valid font files?
...o follow a few specific steps which are not necessarily straightforward in order to save the extracted font data as a file which is re-usable.
Using mupdf
Next, MuPDF. This application comes with a utility called pdfextract (on Windows: pdfextract.exe) which can extract fonts and images from PDFs. ...
Java Class that implements Map and keeps insertion order?
...uggest a LinkedHashMap or a TreeMap. A LinkedHashMap keeps the keys in the order they were inserted, while a TreeMap is kept sorted via a Comparator or the natural Comparable ordering of the elements.
Since it doesn't have to keep the elements sorted, LinkedHashMap should be faster for most cases; ...
Is the order of iterating through std::map known (and guaranteed by the standard)?
...l iterate consequently through the elements with keys, sorted in ascending order?
6 Answers
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Select first row in each GROUP BY group?
...OW_NUMBER() OVER(PARTITION BY p.customer
ORDER BY p.total DESC) AS rk
FROM PURCHASES p)
SELECT s.*
FROM summary s
WHERE s.rk = 1
Supported by any database:
But you need to add logic to break ties:
SELECT MIN(x.id), -- change to MAX if you want the hi...
MySQL select one column DISTINCT, with corresponding other columns
...terminate.". In practice I've successfully used this kind of queries with ORDER BY clause, for instance you could add ORDER BY id ASC/DESC and MySQL would return consistent results every time you would execute the query. But i would be sure whether anyone should use undocumented features in product...