3_16.cpp

#include <iostream>
#include <vector>
#include <string>

using namespace std;

int main(void)
{
    vector<int> v1;
    vector<int> v2(10);
    vector<int> v3(10, 42);
    vector<int> v4{10};
    vector<int> v5{10, 42};
    vector<string> v6{10};
    vector<string> v7{10, "hi"};

    cout<<"v1的元素个数是: "<<v1.size()<<endl;
    if(v1.size() > 0)
    {
        cout<<"v1的元素分别是: "<<endl;
        for(auto mem : v1)
            cout<<mem<<" ";
        cout<<endl;
    }

    cout<<"v2的元素个数是: "<<v2.size()<<endl;
    if(v2.size() > 0)
    {
        cout<<"v2的元素分别是: "<<endl;
        for(auto mem : v2)
            cout<<mem<<" ";
        cout<<endl;
    }

    cout<<"v3的元素个数是: "<<v3.size()<<endl;
    if(v3.size() > 0)
    {
        cout<<"v3的元素分别是: "<<endl;
        for(auto mem : v3)
            cout<<mem<<" ";
        cout<<endl;
    }

    cout<<"v4的元素个数是: "<<v4.size()<<endl;
    if(v4.size() > 0)
    {
        cout<<"v4的元素分别是: "<<endl;
        for(auto mem : v4)
            cout<<mem<<" ";
        cout<<endl;
    }

    cout<<"v5的元素个数是: "<<v5.size()<<endl;
    if(v5.size() > 0)
    {
        cout<<"v5的元素分别是: "<<endl;
        for(auto mem : v5)
            cout<<mem<<" ";
        cout<<endl;
    }
    cout<<"v6的元素个数是: "<<v6.size()<<endl;
    if(v6.size() > 0)
    {
        cout<<"v6的元素分别是: "<<endl;
        for(auto mem : v6)
            cout<<mem<<" ";
        cout<<endl;
    }

    cout<<"v7的元素个数是: "<<v7.size()<<endl;
    if(v7.size() > 0)
    {
        cout<<"v7的元素分别是: "<<endl;
        for(auto mem : v7)
            cout<<mem<<" ";
        cout<<endl;
    }

    return 0;
}