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C Program to Implement Depth First Search Traversal using Post Order
/* C Program to Implement Depth First Search Traversal using Post Order */
/*
50
/ \
20 30
/ \
70 80
/ \ \
10 40 60
(50, 20, 30, 70, 80, 10, 40, 60)
*/
#include <stdio.h>
#include <stdlib.h>
struct btnode {
int value;
struct btnode *l;
struct btnode *r;
};
typedef struct btnode bt;
bt *root;
bt *new, *list;
bt *create_node();
void display(bt *);
void construct_tree();
void dfs(bt *);
void main()
{
construct_tree();
display(root);
printf("\n");
printf("Depth first traversal\n ");
dfs(root);
}
/* Creates an empty node */
bt * create_node()
{
new=(bt *)malloc(sizeof(bt));
new->l = NULL;
new->r = NULL;
}
/* Constructs a tree */
void construct_tree()
{
root = create_node();
root->value = 50;
root->l = create_node();
root->l->value = 20;
root->r = create_node();
root->r->value = 30;
root->l->l = create_node();
root->l->l->value = 70;
root->l->r = create_node();
root->l->r->value = 80;
root->l->r->r = create_node();
root->l->r->r->value = 60;
root->l->l->l = create_node();
root->l->l->l->value = 10;
root->l->l->r = create_node();
root->l->l->r->value = 40;
}
/* Display the elements in a tree using inorder */
void display(bt * list)
{
if (list == NULL)
{
return;
}
display(list->l);
printf("->%d", list->value);
display(list->r);
}
/* Dfs traversal using post order */
void dfs(bt * list)
{
if (list == NULL)
{
return;
}
dfs(list->l);
dfs(list->r);
printf("->%d ", list->value);
}
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