#include <iostream>

using namespace std;
struct btree{
int val;
btree *ltree;
btree *rtree;
};
btree *t;

void create(btree* &t,int n){
    if(t == NULL){
                t = new btree;
                t->val = n;
                t->ltree = NULL;
                t->rtree = NULL;
                if((n+1) < 10){
                        create(t->ltree,n+1);
                }
                if((n+2) < 10){
                        create(t->rtree,n+2);
                }
        }
}
void visit(btree* &t){
        if(t != NULL){
                cout << t->val << '\t';
                visit(t->ltree);
                visit(t->rtree);
        }
}

void dbl(btree* &t){
        if (t!= NULL){
                if(t->val%2 != 0){
                        t->val = t->val*2;
                }
                dbl(t->ltree);
                dbl(t->rtree);
        }
}

int sommafoglie(btree* &t){
    if(t == NULL)return 0;


	if(t->ltree == NULL && t->rtree == NULL)
		return t->val;
	return sommafoglie(t->ltree) + sommafoglie(t->rtree);
}


int main()
{int n;
t=NULL;
create(t,6);
//visit(t);
dbl(t);
visit(t);

//cout<<sommafoglie(t);
    return 0;
}