Alternanza pari - dispari (posizione) inseriti in l3

function new_list(l1,l2,l3)
{
    var dim1=0,dim2=0,p1,p2,p3,c1=1,c2=1,r1={x:null,succ:null},r2={x:null,succ:null};
        if(l1==null||l2==null){return;}
            while(p1!=null){p1=p1.succ;dim1++;}
            while(p2!=null){p2=p2.succ;dim2++;}
                if(dim1>dim2){for(p1=l1.testa;p1!=null;p1=p1.succ)
                {
                    c1++;if(c1%2!==0)
                        { r1={x:p1.x}; p3=l3.testa;
                            if(p3==null){l3.testa=r1;}
                            else
                                { while(p3.succ!=null){p3=p3.succ;}
                                    p3.succ=r1;
                                    p3=p3.succ;
                                }
                        } for(p2=l2;p2!=null;p2=p2.succ)
                            {
                                c2++; if(c2%2===0){ r2={x:p2.x};
                                    p3.succ=r2;
                                    p3=p3.succ;
                } else
                                {
                                    for(p1=l1.testa;p1!=null;p1=p1.succ)
                                        {
                                            c1++;if(c1%2===0)
                                            { r1={x:p1.x};p3=l3.testa;
                                                if(p3==null){l3.testa=r1;}
                                                else
                                                { while(p3.succ!=null){p3=p3.succ;}
                                                    p3.succ=r1;
                                                    p3=p3.succ;
                                                }
                                            } for(p2=l2.testa;p2!=null;p2=p2.succ)
                                                {
                                                    c2++;if(c2%2!==0)
                                                        { r2={x:p2.x};
                                                            p3.succ=r2;
                                                            p3=p3.succ;}
                                                        }
                                                }
                                        }
                                }
}
                             }
}