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List of Big-O for PHP functions

...all: Thanks! I did a bit of reading and it turns out PHP uses 'nested' hashtables for collisions. That is, instead of a logn structure for collisions it simply uses another hashtable. And I do understand that practically speaking PHP hashtables give O(1) performance, or at least O(1) on average - t...
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What is the best place for storing uploaded images, SQL database or disk file system? [closed]

...ll consume a lot of memory. Also, if you use a storage engine that employs table-locks for writes (ISAM for example), your files table might be locked often depending on the size / rate of files you are storing there. Regarding security - I usually store the files in a directory that is outside of...
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What is the fastest factorial function in JavaScript? [closed]

...proach make sure to convert to exponential before using the aforementioned table. – David Scott Kirby May 2 '14 at 20:36 ...
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Parsing a comma-delimited std::string [duplicate]

...der: std::ctype<char> { csv_reader(): std::ctype<char>(get_table()) {} static std::ctype_base::mask const* get_table() { static std::vector<std::ctype_base::mask> rc(table_size, std::ctype_base::mask()); rc[','] = std::ctype_base::space; rc['\n'] = ...
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Hibernate: hbm2ddl.auto=update in production?

...ddl hardly can predict (such as disabling triggers that were installed for table being modified). For complex schemas the safest way is manual. Automatic with post-regression testing is distant second. All IMHO. – Vladimir Dyuzhev Oct 21 '08 at 14:06 ...
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C++ performance challenge: integer to std::string conversion

... first one is a fun implementation that doesn't use any precomputed lookup tables or explicit division/modulo. This one is competitive with the others with gcc and with all but Timo's on msvc (for a good reason that I explain below). The second algorithm is my actual submission for highest performan...
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What is the Java string pool and how is “s” different from new String(“s”)? [duplicate]

...storing only one copy of each distinct string value, which must be immutable. Interning strings makes some string processing tasks more time- or space-efficient at the cost of requiring more time when the string is created or interned. The distinct values are stored in a string inter...
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How to print colored text in Python?

... On Linux, you might want to use tput, like so since it results in more portable code. – Martin Ueding Nov 3 '12 at 11:04 3 ...
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Floating elements within a div, floats outside of div. Why?

...to support old browsers, or using other block-level displays like display: table. Solution: BFC roots There is an exception to the problematic behavior defined at the beginning: if a block element establishes a Block Formatting Context (is a BFC root), then it will also wrap its floating contents....
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Is it possible to modify variable in python that is in outer, but not global, scope?

...esides the global (module) scope. For python 2, I usually just use a mutable object (like a list, or dict), and mutate the value instead of reassign. example: def foo(): a = [] def bar(): a.append(1) bar() bar() print a foo() Outputs: [1, 1] ...