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Hexadecimal To Decimal in Shell Script

...var4; var5=$(($var4-$var3)) bash: -: syntax error: operand expected (error token is "-") That could happen because the value given to bc was incorrect. That might well be that bc needs UPPERcase values. It needs BFCA3000, not bfca3000. That is easily fixed in bash, just use the ^^ expansion: var3...
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Static constant string (class member)

...lation unit only const char A::RECTANGLE[] = "rectangle"; There! No heap allocation, no copying, no dynamic initialization. Cheers, s. share | improve this answer | follow...
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How can I initialize base class member variables in derived class constructor?

...onstructor. It will first be default-initialized when the instance of B is allocated, then it will be assigned inside the B's constructor. But I also think the compiler can still optimize this. – Violet Giraffe Jan 10 '19 at 11:36 ...
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How do I apply the for-each loop to every character in a String?

...cost penalty. From the documentation: [toCharArray() returns] a newly allocated character array whose length is the length of this string and whose contents are initialized to contain the character sequence represented by this string. There are more verbose ways of iterating over characters i...
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Reference — What does this symbol mean in PHP?

... constants: Although these are not just symbols but important part of this token family. There are eight magical constants that change depending on where they are used. __LINE__: The current line number of the file. __FILE__: The full path and filename of the file. If used inside an include, the n...
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Reducing Django Memory Usage. Low hanging fruit?

...our browser at http://domain/_dozer/index to see a list of all your memory allocations. I'll also just add my voice of support for mod_wsgi. It makes a world of difference in terms of performance and memory usage over mod_python. Graham Dumpleton's support for mod_wsgi is outstanding, both in ter...
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Null check in an enhanced for loop

... Note that Collections.emptyList() will avoid allocating an extra object (IIRC). – Jon Skeet Feb 12 '10 at 6:31 7 ...
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How do you remove all the options of a select box and then add one option and select it with jQuery?

...s create a memory leak? The option elements are now inaccessible but still allocated. – Synetech Mar 6 '19 at 19:57 add a comment  |  ...
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From io.Reader to string in Go

...ing about "the most efficient way". Currently, the Go run-time will always allocate a new string when converting []byte to string. The reason for this is that the compiler doesn't know how to determine whether the []byte will be modified after the conversion. There is some room for compiler optimiza...
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Dynamically changing font size of UILabel

...loat)i]; NSAttributedString *attributedText = [[NSAttributedString alloc] initWithString:text attributes:@{NSFontAttributeName: font}]; CGRect rectSize = [attributedText boundingRectWithSize:CGSizeMake(self.frame.size.width, CGFLOAT_MAX) options:NSStringDrawingUsesLineFragmentOrigin...