String Format Specifiers

https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/Strings/Articles/formatSpecifiers.html

Type	Format specifier	Considerations
NSString	%@	Objective-C object, printed as the string returned by descriptionWithLocale: if available, or description otherwise. Also works with CFTypeRef objects, returning the result of the CFCopyDescription function.
int	%d, %D	Signed 32-bit integer (int).
(unsigned int	%u, %U	Unsigned 32-bit integer (unsigned int).
double	%f	64-bit floating-point number (double).
(unsigned int	%u, %U	Unsigned 32-bit integer (unsigned int).
NSInteger	%ld or %lx	Cast the value to long.
NSUInteger	%lu or %lx	Cast the value to unsigned long.
CGFloat	%f or %g	%f works for floats and doubles when formatting; but note the technique described below for scanning.
CFIndex	%ld or %lx	The same as NSInteger.
pointer	%p or %zx	%p adds 0x to the beginning of the output. If you don't want that, use %zx and no typecast.

相关链接：
NSlog警告—— 编译器打印NSInteger类型