用vector构造自动扩容的二维数组

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

int main()
{
    vector<vector<string> > edge; //注意<string>后有一个空格符号
    vector<string> stemp(2);      //将列的个数设置为2
　　
    for(int i = 0;i<5;i++)        //此处参数5表示将行数设置为5
    {
        cin>>stemp[0]>>stemp[1];
        edge.push_back(stemp);
    }

    for(int j=0;j<edge.size();j++)
    {
        cout<< j+1<<": "<<edge[j][0]<<" , "<<edge[j][1]<<endl;
    }return 0;
}

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

int main()
{
    vector<vector<int> > a;
    vector<int> stmp(5);          //set the colCount=5
    for (int i = 0; i < 45; i++)  //set the rowCount=5
    {
        for (int j = 0; j < 5;j++)
        {
            stmp[j] = (i+1)*(j+1);
            cout << stmp[j] << " ";
        }
        cout << endl;
        a.push_back(stmp);
    }
    int rowCount = a.size();     //get the rowCout from a two-dimensional array
    int cloCount = a[0].size();  //get the colCout from a two-dimensional array
    cout << "row: " << rowCount << endl;
    cout << "col: " << cloCount << endl;
    return 0;
}

//注：如果二维数组是如 int a[15][8]定义的，则通过如下方法获取行列数

cout << sizeof(a)/sizeof(a[0]) << endl;  //行数outpuut 15
cout << sizeof(a[0]) / sizeof(a[0][0]) << endl; //列数outpuut 8