stl操作4

容器大小的操作

 c.size()      c.max_size()     c.empty()     c.resize(n)     c.resize(n,t)

注意：resize操作可能会是迭代器失效

#include <iostream>#include <vector>#include <list>#include <deque>using namespace std;int main( int argc, char ** argv ){list<int> lst;lst.push_back(10);lst.push_back(20);lst.push_back(30);cout<<"size: "<<lst.size()<<endl;list<int>::size_type count = lst.size();cout<<"size_type size: "<<count<<endl;cout<<"max_size: "<<lst.max_size()<<endl;if( not lst.empty() ){cout<<"not empty"<<endl;}else{cout<<"empty"<<endl;}lst.resize(10);for(list<int>::iterator itr = lst.begin(); itr!=lst.end(); ++itr ){cout<<*itr<<endl;}lst.resize(20,-1);for(list<int>::iterator itr = lst.begin(); itr != lst.end(); ++itr ){cout<<*itr<<endl;}lst.resize(2);for(list<int>::iterator itr = lst.begin(); itr != lst.end(); ++itr ){cout<<*itr<<endl;}return 0;}