Efficiency Items

I considered including a chapter on efficiency in Effective STL, but I ultimately decided that the current organization was preferable. Still, a number of Items focus on minimizing space and runtime demands. For your performance-enhancing convenience, here is the table of contents for the virtual chapter on efficiency:

Item 4:	Call empty instead of checking size() against zero.	23
Item 5:	Prefer range member functions to their single-element counterparts.	24
Item 14:	Use reserve to avoid unnecessary reallocations.	66
Item 15:	Be aware of variations in string implementations.	68
Item 23:	Consider replacing associative containers with sorted vectors.	100
Item 24:	Choose carefully between map::operator[] and map::insert when efficiency is important.	106
Item 25:	Familiarize yourself with the nonstandard hashed containers.	111
Item 29:	Consider istreambuf_iterators for character-by-character input.	126
Item 31:	Know your sorting options.	133
Item 44:	Prefer member functions to algorithms with the same names.	190
Item 46:	Consider function objects instead of functions as algorithm parameters.	201