#include<conio.h>

#include<iostream.h>

#include<stdio.h>

typedef struct NUT

{

int Dulieu;

NUT * Left,* Right;

} ;

typedef NUT*Cay;

// cau 1

NUT*Taonut(int x,NUT*L,NUT*R)

{

NUT*e=new NUT;

e->Dulieu=x;

e->Left=L;

e->Right=R;

return e;

}

// cau 2

void Taocay(Cay & t)

{

NUT*m,*h,*b,*s;

m=Taonut(22,NULL,NULL);

h=Taonut(23,m,NULL);

s=Taonut(27,NULL,NULL);

b=Taonut(25,h,s);

t=b;

}

//cau 3

void Duyetphai(Cay t)

{

if(t!=NULL)

{

Duyetphai(t->Right);

cout<<t->Dulieu<<"  ";

Duyetphai(t->Left);

}

}

//cau 4

int Demnut(Cay t)

{

if(t==NULL)

return 0;

else

return 1+Demnut(t->Right)+Demnut(t->Left);

}

// cau 5

void Them(int x, Cay & t)

{

NUT*e=new NUT;

e->Dulieu=x;

e->Left=NULL;

e->Right=NULL;

if(t==NULL)

t=e;

else

 if(x<t->Dulieu)

 Them(x,t->Left);

   else

    if(x>t->Dulieu)

     Them(x,t->Right);

      else

       cout<<" da co x tren cay";

}

// cau 6

int Tong(Cay t)

{

int S=0;

if(t!=NULL)

 S+=t->Dulieu+Tong(t->Left)+Tong(t->Right);

 return S;

 }

//cau 7

int Demla(Cay t)

{

if(t==NULL)

 return 0;

 else

 {

  if((t->Left==NULL) &&( t->Right==NULL))

   return 1;

   else

    return Demla(t->Left)+Demla(t->Right);

}

}

 void Duyettrai(Cay t)

{

if(t!=NULL)

{

Duyettrai(t->left);

cout<<t->Dulieu<<"  ";

Duyettrai(t->right);

}

}

 void Duyetgiua(Cay t)

{

if(t!=NULL)

{

cout<<t->Dulieu<<"  ";

Duyetgiua(t->Left);

Duyetgiua(t->Right);

}

}

void main()

{

clrscr();

Cay t;

Taocay(t);

Duyetphai(t);

int S;

S=Tong(t);

cout<<"

tong cay ="<<S;

int a,b;

b=Demla(t);

cout<<"

so la cay ="<<b;

a=Demnut(t);

cout<<"

so nut cua cay la "<<a;

cout<<"

them 20 vao cay";

Them(20,t);

Duyetphai(t);

b=Demla(t);

cout<<"

so la cay sau khi chen ="<<b;

a=Demnut(t);

cout<<"

so nut sau khi them la "<<a;

S=Tong(t);

cout<<"

Tong sau khi them ="<<S;

getch();

}