void print()
{
    int i,j,k,l;
    phonebook swap_;
    for (i=0 ; i < counter; i++)
    {
        for (j=0; j < counter-1; j++)
        {
            if (strcmpi(person[j].lname,person[j+1].lname)>0)
            {
                swap_=person[j];
                person[j]=person[j+1];
                person[j+1]=swap_;
            }
            else if(strcmpi(person[j].lname,person[j+1].lname)==0)
            {
                if (strcmpi(person[j].fname,person[j+1].fname)>0)
                {
                    swap_=person[j];
                    person[j]=person[j+1];
                    person[j+1]=swap_;
                }
                else if(strcmpi(person[j].fname,person[j+1].fname)==0)
                {
                    if(strcmp(person[j].number,person[j+1].number)>0)
                    {
                        swap_=person[j];
                        person[j]=person[j+1];
                        person[j+1]=swap_;
                    }
                }
            }
            else
                continue;
        }
    }
    system("cls");
    for (i=0 ; i <counter; i++)
        printf("%d)\nfirst name: %s\nlast name: %s\nAddress: %s\nCity: %s\nNumber: %s\n",i+1,person[i].fname,person[i].lname,person[i].address,person[i].city,person[i].number);
}