c++ vector 迭代器 demo

#include<iostream>
#include<vector>
using namespace std;

int main()
{
vector<int> v(5);
cout<<"sizeof(v)="<<sizeof(v)<<endl;
v[0] =200;
v[1] =200;
v[2] =200;
v[3] =200;
v[4] =200;
cout<<"1 v.size()="<<v.size()<<endl;
v.push_back(500);
cout<<"2 v.size()="<<v.size()<<endl;
int i;
for(i=0;i<6;i++)
cout<<v[i]<<" ";
cout<<endl;
return 0;
}

#include<iostream>
#include<vector>
using namespace std;

int main()
{
vector<int> v(5);
cout<<"sizeof(v)="<<sizeof(v)<<endl;
v[0] =200;
v[1] =200;
v[2] =200;
v[3] =200;
v[4] =200;
cout<<"1 v.size()="<<v.size()<<endl;
v.push_back(500);
cout<<"2 v.size()="<<v.size()<<endl;
#if 0
int i;
for(i=0;i<6;i++)
cout<<v[i]<<" ";
cout<<endl;
#else
for(auto k:v)
cout<<k<< " ";
cout<<endl;
#endif
//迭代器
vector<int>::iterator it;
for(it = v.begin();it != v.end();++it)
cout<<*it<<" ";
cout<<endl;

return 0;
}