https://gist.github.com/247b71b582074c5284ac6028d4a9f2b0

TreeEX1.c

#include "stdio.h"
#include "stdlib.h"

struct NODE
{
	int Data;
	struct NODE *left, *right;	
};

typedef struct NODE *NODEPTR;

void Insert (NODEPTR *t, int x)
{
	if (!*t)
	{
		*t=(NODEPTR)malloc(sizeof(struct NODE));
		(*t)->Data=x;
		(*t)->left=(*t)->right=NULL;
	}
	else (x>(*t)->Data)?Insert(&((*t)->left), x): Insert(&((*t)->right),x);/*Thay the "<" voi yeu cau sau*/
}

void InTree(NODEPTR *t)
{
	int x;
	printf("Nhap so 0 de dung\n");
	do
	{
		scanf("%d",&x);
		if (x) Insert(t,x);
	}while(x);
}

void OutTree(NODEPTR t, char label, int d)
{
	if (t)
	{
		OutTree(t->right, 'L', d+1);
		printf("%*c[%c%d]\n",2*d, ' ', label, t->Data );
		OutTree(t->left, 'R', d+1);
	}
}

int main()
{
	NODEPTR	t=NULL;
	InTree(&t);
	printf("\nCay goc: \n");
	OutTree(t, '*', 1);
	printf("Nhap vao gia tri can chen: ");
	int x;
	scanf("%d", &x);
	Insert(&t, x);
	printf("\nCay goc: \n");
	OutTree(t, '*', 1);
	return 0;
}