Day22.cpp

/*Traversal of a binary tree: 
1.Preorder traversal (Root->Left subtree->Right subtree)
2. Inorder traversal: Left subtree, Root, Right Subtree
3. Postorder traversal: Left subtree, Right subtree, root
*/
#include <bits/stdc++.h>
using namespace std;


struct Node{//Difference between class and structures
    int data;
    struct Node* left;
    struct Node* right;

    Node(int val){
        data=val;
        left=NULL;
        right=NULL;
    }
};

void preorder(struct Node* root){

    if(root==NULL) return;
    cout<<root->data<<" ";
    preorder(root->left);
    preorder(root->right);
}

void inorder(struct Node* root){
    if(root==NULL) return;
    inorder(root->left);
    cout<<root->data<<" ";
    inorder(root->right);
}

void postorder(struct Node* root){
    if(root==NULL) return;
    postorder(root->left);
    postorder(root->right);
    cout<<root->data<<" ";
}

//Building a tree from preorder & inorder


int main(){
    struct Node* root=new Node(1);
    root->left=new Node(2);
    root->right =new Node(3);

    root->left->left=new Node(4);
    root->left->right=new Node(5);
    root->right->left= new Node(6);
    root->right->right= new Node(7);
    /* 1
    2     3
   4  5 6   7
    */
   preorder(root);
   cout<<endl;
   inorder(root);
   cout<<endl;
   postorder(root);
    return 0;
}