Newbie NSString assignment solving two kinds of differences

 
NSString * a = @ "something"; 
NSString * b = [[NSString alloc] initWithFromat: @ "something"]; 
NSLog (@ "% d", [a retainCount]); 
NSLog (@ "% d", [b retainCount]); 

What are the specific differences between the above two assignment methods; and why the first number is very large, a novice again sincerely thank
Reply:
The first is a constant, there will be books on the basis of objective-c
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The first should be autorelease, the second is to manually release the memory
Reply:

cited a floor glacier3d reply:

first is a constant, there will be

NSString object type, it is a constant not correct, but the second floor of argument is correct, because the string instance "a" is a system initialization is completed, so bring a return AutoRelease (automatic release mechanism pool), and character Examples string "b" is instantiated and given initial manual, enough its reference base plus 1.
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If you want to test retain count, please do not take NSString test.
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The first one is the automatic release of the second memory address via a method first statement in the format string
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Those who do not explicitly write objects are created Alloc Autorelease object.
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reference to the second floor superboy1119 reply:

first one should be autorelease, the second is to manually release memory

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Is this. First, the system will default to autorelease, to help you relieve it

The second, is to release his own
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reference to the third floor wzq352 reply:

cited a floor glacier3d reply:
The first is a constant, there will
book on the basis of objective-c

NSString object type, it is a constant not correct, but the second floor of argument is correct, because the string instance "a" is a system initialization is completed, so bring a return AutoRelease (automatic release mechanism pool), and character Examples string "b" is instantiated and given initial manual, enough its reference base plus 1.

+1
Reply:
Const string reference count is 0x7fffffff, which means that it is never released.