74 lines
1.4 KiB
C++
74 lines
1.4 KiB
C++
#include<iostream>
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#include<queue>
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#define endl "\n"
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using namespace std;
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// Basic Structure of a Tree
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struct Node{
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int data;
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struct Node *left;
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struct Node *right;
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Node(int val){
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data = val;
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left = NULL;
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right = NULL;
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}
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};
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/* Level order Traversal of a Binary Tree using Queue */
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/* Complexity : O(n) */
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// Here NULLs are used to keep track of levels
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void level_order(Node* root){
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if(root == NULL)
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return;
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queue<Node*> q;
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q.push(root); q.push(NULL);
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while(!q.empty()){
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Node* node = q.front();
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q.pop();
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if(node != NULL){
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cout<<node->data<<" ";
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if(node->left)
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q.push(node->left);
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if(node->right)
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q.push(node->right);
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}else if(!q.empty()){
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q.push(NULL);
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}
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}
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cout<<endl;
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}
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int main(){
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Node* root = new Node(1);
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root->left = new Node(2);
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root->right = new Node(3);
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root->left->left = new Node(4);
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root->left->right = new Node(5);
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root->right->right = new Node(7);
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/*
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1
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/ \
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2 3
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/ \ \
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4 5 7
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Expected-> level-order : 1,2,3,4,5,7
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*/
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cout<<"Level Order is : ";
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level_order(root);
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return 0;
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} |