int array[5]={1,2,3,4,5};for(int&D : array){
D *=2;}
//使用auto,自动获取类型for(auto&D : array){
D *=2;}
//for_each()template<classInputIterator,classFunction>
Function for_each(InputIterator first, InputIterator last, Function fn){while(first!=last){
fn (*first);++first;}return fn;// or, since C++11: return move(fn);}