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

char in[]= {'d','b','e','a','f','c','g'};
char pre[]={'a','b','d','e','c','f','g'};
int size = sizeof(in);
int pos = 0;

typedef struct node{
	char value;
	struct node*left;
	struct node*right;
}treenode;

treenode* get_tree(int l,int r);
void print(treenode*root);
int search(char val);

void print(treenode*root)
{
	if(root==NULL)
	return;
	print(root->left);
	printf("%c",root->value);
	print(root->right);
}

int search(char val)
{
	int i;
	for(i=0;i<size;i++)
	{
		if(in[i]==val)
		return i;
	}
	return -1;
}

treenode* get_tree(int l, int r)
{
	int inpos = search(pre[pos]);
	if(l>=r)return NULL;
	pos++;
	treenode* temp = (treenode*)malloc(sizeof(struct node));   
	temp->value = in[inpos];
	temp->left = get_tree(l,inpos);
	temp->right = get_tree(inpos+1,r);
	return temp;
}
	 
int main()
{
	
	treenode*root = NULL;
	int l = 0;
	root = get_tree(l,size);
    print(root);
    printf("\n");
	return 0;
}