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#include<stdlib.h>
#include<stdio.h>

struct tree
{struct tree*left;
int data;
struct tree*right;

};
typedef struct tree treenode;
typedef treenode *b_tree


b_tree insert_node(b_tree root,int node)
{
b_tree nnode;
b_tree cnode;
b_tree pnode;
nnode=(b_tree)malloc(sizeof(treenode));
nnode->node=node;
nnode->right=NULL;
nnode->left=NULL;

if(root==NULL)
return nnode;
else
{
cnode=root;
while(cnode!=NULL)
{
  pnode=cnode;
  if(cnode->data>node)
  cnode=cnode->left;
  else
  cnode=cnode->right;
}
if(pnode->data>node)
pnode->left=nnode;
else
pnode->right=nnode;
}
return root;
}

b_tree create_btree(int*data,int len)
{
b_tree root=NULL;
int i;
for(i=0;i<len;i++)
root=insert_node(root,data[i]);
return root;
}

void inorder(b_tree point)
{
if(point!=NULL)
{
inorder(point->left);
printf("%d",point->data);
inorder(point->right);
}

}

void main()
{
b_tree root=NULL;
inti,j;
int value;
int nodelist[20];
printf("\n please input the letter(exit for 0):\n");
j=0;
scanf("%d",&value);
while(j!=0)
{
nodelist[j]=value;
j=j+1;
scanf("%d",&value);

}

root=create_btree(nodelist,j);
printf("\n the ordertrv result is:\n");
inorder(root);
printf("\n")
}