二维动态数组

方法一：new

     int row,column;
     cin >> row >> column;
     //申请空间
     int **a =  new int* [row];    
     for(int i = 0; i < row; i++)
         a[i] = new int[column];

方法二：vector

     int row,column;  
     cin>>row>>column;  
     //申请空间  
    vector<vector<int> > a(row,vector<int>(column));