Re: vector of vectors

On 02/12/14, Frank wrote:


I had to fill in some stuff and ended up with the following example:

#include <vector>
#include <algorithm>

template< typename VEC2_ELEMENT // element type
 >
class vec2 : public std::vector <std::vector<VEC2_ELEMENT> >
{
public:
     // something here

     int longestindex() {
         int retval;
         int maxSoFar = -1;
         for (int i = 0; i < this->size(); ++i) {
             int currentSize = this->operator[] (i).size ();
             if (maxSoFar < currentSize) {
                 maxSoFar = currentSize;
                 retval = i;
             }
         }
         return retval;
     }

     // longest returns the # of elements of the sub-vector
     // with the most elements
     int longest()
     {
         if (this->size() > 0)
         {
             // longestindex returns the index of the sub-vector
             // with the most elements
             int index = this->longestindex();
// return this->at(index).size(); // works
             return (*this)[longestindex()].size(); // doesn't work
         }
         else
             return -1;
     }
} ;

int main () {
     vec2<int> foo;
     foo.push_back(std::vector<int> (3));
     foo.push_back(std::vector<int> (8));
     foo.push_back(std::vector<int> (5));
     int retval = foo.longest();
}

I just took it as a simple coding exercise for the evening :-)

 > Sorry, where are my manners...
 > many thanks for your effort.

You're welcome.
Stuart