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Add UIPickerView & a Button in Action sheet - How?

...segmented control (eyecandy) UIActionSheet *actionSheet = [[UIActionSheet alloc] initWithTitle:nil delegate:nil cancelButtonTitle:nil destruct...
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In C++, is it still bad practice to return a vector from a function?

...end(), sum2); } In the first example, there are many unnecessary dynamic allocations/deallocations happening, which are prevented in the second example by using an output parameter the old way, reusing already allocated memory. Whether or not this optimization is worth doing depends on the relativ...
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MySQL high CPU usage [closed]

...db_buffer_pool_size (if you're using innodb tables) as all of these memory allocations can have an affect on query performance which can cause MySQL to eat up CPU. You'll also probably want to give the following a read over as they contain some good information. How MySQL Uses Memory MySQL System...
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Is it better to call ToList() or ToArray() in LINQ queries?

...straints you should use ToList. In the majority of scenarios ToArray will allocate more memory than ToList. Both use arrays for storage, but ToList has a more flexible constraint. It needs the array to be at least as large as the number of elements in the collection. If the array is larger, th...
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iOS 7 TableView like in Settings App on iPad

...lor = UIColor.clearColor; CAShapeLayer *layer = [[CAShapeLayer alloc] init]; CGMutablePathRef pathRef = CGPathCreateMutable(); CGRect bounds = CGRectInset(cell.bounds, 10, 0); BOOL addLine = NO; if (indexPath.row == 0 && indexPath.r...
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In Visual Studio C++, what are the memory allocation representations?

...g/wiki/Magic_number_(programming) * 0xABABABAB : Used by Microsoft's HeapAlloc() to mark "no man's land" guard bytes after allocated heap memory * 0xABADCAFE : A startup to this value to initialize all free memory to catch errant pointers * 0xBAADF00D : Used by Microsoft's LocalAlloc(LMEM_FIXED) t...
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What is meant by Resource Acquisition is Initialization (RAII)?

...object. ** Update2: as @sbi pointed out, the resource - although often is allocated inside the constructor - may also be allocated outside and passed in as a parameter. share | improve this answer ...
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Formatting NSDate into particular styles for both year, month, day, and hour, minute, seconds

... this is what i used: NSDateFormatter *dateFormat = [[NSDateFormatter alloc] init]; [dateFormat setDateFormat:@"yyyy-MM-dd"]; NSDateFormatter *timeFormat = [[NSDateFormatter alloc] init]; [timeFormat setDateFormat:@"HH:mm:ss"]; NSDate *now = [[NSDate alloc] init]; NSString *theDate = [dateFo...
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What are the barriers to understanding pointers and what can be done to overcome them? [closed]

...e array. In memory, there will be some overhead associated with the house allocation, I'll illustrate this below like this: ---[ttttNNNNNNNNNN]--- ^ ^ | | | +- the FName array | +- overhead The "tttt" area is overhead, there will typically be more of this for vari...
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Proper stack and heap usage in C++?

... It's lifespan: any local variable inside a function (anything you do not malloc() or new) lives on the stack. It goes away when you return from the function. If you want something to live longer than the function that declared it, you must allocate it on the heap. class Thingy; Thingy* foo( ) { ...