IOS: NSString split

I have this NSString开发者_如何学Python:

NSString *perc = @"- 20 %";

I want only "20 %".

What can I do?

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[perc subStringFromIndex:2];

There are different functions for substrings, take a look at them either typing "subString" and getting xcode help, or in traditional way - from doc :)