2_18_5_2016

#include<iostream>
using namespace std;
#include<fstream>
struct nodo{int info; nodo* left,*right;nodo(int a=0, nodo* b=0, nodo* c=0){info=a; left=b; right=c;}};

int conta_nodi(nodo* R)
{
    if(!R)
        return 0;
    if(!R->left && !R->right)
        return 1;
    return conta_nodi(R->left)+conta_nodi(R->right)+1;
}

nodo* insert(nodo*R, nodo* n)
{
    if(!R)
        return n;
    if(conta_nodi(R->left)<=conta_nodi(R->right))
        R->left=insert(R->left, n);
    else
        R->right=insert(R->right, n);
    return R;
}

nodo* build_tree(nodo* R,int n_el)
{
    if(!n_el)
        return R;
    int x;
    cin>>x;
    nodo* n=new nodo(x);
    nodo* z=insert(R,n);
    return build_tree(z, n_el-1);
}

void stampa(nodo *r)
{
  if(r)
    {
      cout<<r->info<<'(';
      stampa(r->left);
      cout<<',';
      stampa(r->right);
      cout<<')';
    }
  else
    cout<< '_';
}
 main()
{
 int n_el;
 cin>>n_el;

 nodo* R=build_tree(0,n_el);
 stampa(R);
 cout<<endl<<"end"<<endl;
}