iPhone NSLog输出格式

%@ Object
%d, %i signed int
%u unsigned int
%f float/double
%x, %X hexadecimal int
%o octal int
%zu size_t
%p pointer
%e float/double (in scientific notation)
%g float/double (as %f or %e, depending on value)
%s C string (bytes)
%S C string (unichar)
%.*s Pascal string (requires two arguments, pass pstr[0] as the first, pstr+1 as the second)
%c character
%C unichar

%lld long long
%llu unsigned long long
%Lf long double