I've this problem: list iterator not dereferencable

[Piojolopez]

Hello guys, I have a problem with this code, the program is the resolution of Sudoku grid, the grid in my program is a vector of STL,and i use a list of STL for the right solution for each cell, to solve my grid i call recursive the function : void risolvi(int indice).
The problem i have is about the iterator, but i don't know how i can fix it, i need your help.
This problem blocks me to come back in to the main function, and so i can't output my solution.
Thank you, and sorry for my bad english

void risolvi(int indice)
{
    list<int> SOLUZIONI;
    list<int >::iterator scorri;
    list<int >::iterator scendi;
    if(indice==81)
    {
 
        vector<int>::iterator scorrimento;
        for(scorrimento=VETTORE.begin(); scorrimento!=VETTORE.end(); scorrimento++)
            cout<<*scorrimento<<endl;        
        cout<<"THE END"<<endl;
    }
    else
    {
        if(verita[indice])
            risolvi(indice+1);
        else
        {
            //list<int> SOLUZIONI;
            for(int s=1;s<=9;s++)
                SOLUZIONI.push_back(s);
            int riga = indice/9, colonna = indice%9;
            int imin = (riga/3)*3;
            int jmin = (colonna/3)*3;
            //ELIMINO GLI ELEMENTI GIA' PRESENTI NEL CUBO 3x3
            for(int rig=imin ; rig < imin+3 ; rig++)
            {
                for(int colonna=jmin ; colonna < jmin+3 ; colonna++)
                    if(VETTORE[9*rig+colonna]!=0)
                        SOLUZIONI.remove(VETTORE[9*rig+colonna]);
            }
            //ELIMINO GLI ELEMENTI GIA' PRESENTI NELLA RIGA
            for(int i=indice%9;i<=(indice%9)+72;i=i+9)
                if(VETTORE[i]!=0)
                    SOLUZIONI.remove(VETTORE[i]);
            //ELIMINO GLI ELEMENTI GIA' PRESENTI NELLA COLONNA
            for(int m=indice/9*9;m<(indice/9*9)+8;m++)
                if(VETTORE[m]!=0)
                    SOLUZIONI.remove(VETTORE[i]);
            //ELIMINA LA PRIMA SOLUZIONE CHE HO CONSIDERATO AL PASSO PRECEDENTE
            //MA CHE IL BACKTRACKING MI HA VALUTATO ERRATA            
            if(backtracking!=appoggio&&SOLUZIONI.size()!=0)
            {
                //list<int>::const_iterator scendi;
                scendi=SOLUZIONI.begin();
                while(*scendi<=numero&&SOLUZIONI.size()!=0)
                //while(SOLUZIONI[1]<=numero && SOLUZIONI.size()!=0)
                    {
                        scendi++;
                        SOLUZIONI.pop_front();
                        if(SOLUZIONI.size()==0)
                        {
                            appoggio=backtracking;
                            do
                            {
                                if(!verita[indice])
                                    VETTORE[indice]=0;
                                indice--;
                            }
                            while(verita[indice]);
                            numero=VETTORE[indice];
                            backtracking++;
                            risolvi(indice);
                        }
                    }            
                    appoggio=backtracking;
            }
            scorri=SOLUZIONI.begin();
            if(SOLUZIONI.size()!=0)
            {
                VETTORE[indice]=*scorri;
                //if (indice==79)
                //    return;
                risolvi(indice+1);
            }        
            else
            {
                appoggio=backtracking;
                do
                {
                    if(!verita[indice])
                        VETTORE[indice]=0;
                    indice--;
                }
                while(verita[indice]);
                numero=VETTORE[indice];
                backtracking++;
                risolvi(indice);
            }
        }
    }
 
}

[gpraghuram]

Hi,
In which line you get the error.
I acnt compile the code locally as some of the declarations are missing.
So post the remaining part of the code so that i can compile and see why the problem is coming

NOTE:
Please use code tags while posting the code

Thanks
Raghuram

[Savage]

Hi,
In which line you get the error.
I acnt compile the code locally as some of the declarations are missing.
So post the remaining part of the code so that i can compile and see why the problem is coming

NOTE:
Please use code tags while posting the code

Thanks
Raghuram

I believe that this is that line:

while(*scendi<=numero&&SOLUZIONI.size()!=0)

,but i don't see any reason for this to not compile.