#define DULJ 100

typedef int TIP;
class elem
{
    public:
        TIP vrij;
        bool used;

        elem()
        {
            used = false;
        }
};  //class elem

struct bt
{
    elem el[DULJ];
};  //struct bt


int ParentB(int n, bt T)
{
    if(!T.el[n].used) return -1;
    if((n % 2) == 0) return (n/2);
    else return((n-1)/2);
}  //int ParentB(int n, bt T)


int LeftChildB(int n, bt T)
{
    if(!T.el[n].used) return -1;
    int r = n * 2;
    if(r > DULJ || !T.el[r].used) return -1;
    else return r;
}  //int LeftChildB(int n, bt T)


int RightChildB(int n, bt T)
{
    if(!T.el[n].used) return -1;
    int r = n * 2 + 1;
    if(r >= DULJ || !T.el[r].used) return -1;
    else return r;
}  //int RightChildB(int n, bt T)


TIP LabelB(int n, bt T)
{
    if(!T.el[n].used) return -1;
    else return T.el[n].vrij;
}  //int LabelB(int n, bt T)


int ChangeLabelB(TIP x, int n, bt &T)
{
    if(!T.el[n].used) return -1;
    else T.el[n].vrij = x;
    return 0;
}  //int ChangeLabelB(int x, int n, bt &T)


int RootB(bt T)
{
    if(!T.el[1].used) return -1;
    else return 1;
}  //int RootB(bt T)


int CreateLeftB(TIP x, int n, bt &T)
{
    if(!T.el[n].used) return -1;
    int r = n * 2;

    if(T.el[r].used || r >= DULJ) return -1;
    T.el[r].used = true;
    T.el[r].vrij = x;
    return 0;
}  //int CreateLeftB(int x, int n, bt &T)


int CreateRightB(TIP x, int n, bt &T)
{
    if(!T.el[n].used) return -1;
    int r = (n * 2) + 1;

    if(T.el[r].used || r >= DULJ) return -1;
    T.el[r].used = true;
    T.el[r].vrij = x;
    return 0;
}  //int CreateRightB(int x, int n, bt &T)


void DeleteB(int n, bt &T)
{
    if(n == -1) return;
    if(!T.el[n].used) return;

    DeleteB(LeftChildB(n, T), T);
    DeleteB(RightChildB(n, T), T);
    T.el[n].used = false;
}  //int DeleteB(int n, bt &T)


void InitB(TIP x, bt &T)
{
    if(T.el[1].used) DeleteB(RootB(T), T);
    T.el[1].used = true;
    T.el[1].vrij = x;
}  //void InitB(int x, bt &T)