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Getting a slice of keys from a map

...eys, k) } } To be efficient in Go, it's important to minimize memory allocations. share | improve this answer | follow | ...
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Try-catch speeding up my code?

...e "ephemeral" -- that is, just pushed and popped on the stack, rather than allocated a specific location on the stack for the duration of the activation. We believe that the JITter will be able to do a better job of register allocation and whatnot if we give it better hints about when locals can be ...
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Difference between string and char[] types in C++

... A char array is just that - an array of characters: If allocated on the stack (like in your example), it will always occupy eg. 256 bytes no matter how long the text it contains is If allocated on the heap (using malloc() or new char[]) you're responsible for releasing the memory...
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Adding the little arrow to the right side of a cell in an iPhone TableView Cell

...exPath Write below code: if (cell ==nil) { cell=[[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier]autorelease]; //For creating custom accessory view with own image UIImageView *accessoryView = [[UIImageView alloc] initWithFrame:CGRec...
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Converting NSString to NSDate (and back again)

...String = @"01-02-2010"; NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init]; [dateFormatter setDateFormat:@"dd-MM-yyyy"]; NSDate *dateFromString = [dateFormatter dateFromString:dateString]; NSDate convert to NSString: NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init]; [d...
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“Application tried to present modally an active controller”?

...trollers instantiated like so: UIViewController* vc1 = [[UIViewController alloc] init]; UIViewController* vc2 = [[UIViewController alloc] init]; UIViewController* vc3 = [[UIViewController alloc] init]; You have added them to a tab bar like this: UITabBarController* tabBarController = [[UITabBarC...
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In C, do braces act as a stack frame?

...[0] here? */ return; } (In other words: is the compiler allowed to deallocate d, even if in practice most don't?). The answer is that the compiler is allowed to deallocate d, and accessing p[0] where the comment indicates is undefined behaviour (the program is not allowed to access the inner ...
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How to remove empty cells in UITableView? [duplicate]

...FooterView = UIView() Objective-C: tableView.tableFooterView = [[UIView alloc] initWithFrame:CGRectZero]; Because the table thinks there is a footer to show, it doesn't display any cells beyond those you explicitly asked for. Interface builder pro-tip: If you are using a xib/Storyboard, you c...
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Apache Spark: The number of cores vs. the number of executors

...ably be set to 63 * 1024 = 64512 (megabytes) and 15 respectively. We avoid allocating 100% of the resources to YARN containers because the node needs some resources to run the OS and Hadoop daemons. In this case, we leave a gigabyte and a core for these system processes. Cloudera Manager helps by ac...
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Efficient string concatenation in C++

...e a look at this interface: template <class charT, class traits, class Alloc> basic_string<charT, traits, Alloc> operator+(const basic_string<charT, traits, Alloc>& s1, const basic_string<charT, traits, Alloc>& s2) You can see that a new object is returne...