{"post":"

Left view and Right view of a binary tree using Iteration

For the left view, we'll traverse each level and print the first node's data of that level and similarly, for the right view, we'll traverse each level and print the data of the last node in that level.

#include<bits/stdc++.h>\nusing namespace std;\nstruct Node{\nint data;\nNode* left;\nNode* right;\nNode(int data){\nthis->data = data;\nleft = right = NULL;\n}\n};
\nvoid printLeftAndRightViewIterative(Node* root){\nif(root == NULL) return;\nqueue<Node*> q;\nq.push(root);\nwhile(!q.empty()){\nint size = q.size();
\n  \tfor(int i = 0; i &lt; size; i++){\n    \tNode* curr = q.front();\n      \tq.pop();\n      \t//if(i == size - 1) cout&lt;&lt;curr-&gt;data&lt;&lt;\" \"; //for right view\n      \tif(i == 0) cout&lt;&lt;curr-&gt;data&lt;&lt;\" \"; //for left view\n      \tif(curr-&gt;left) q.push(curr-&gt;left);\n        if(curr-&gt;right) q.push(curr-&gt;right);\n    }\n}\n
\n}
\nint main() {\n/*\n1\n/    
\n2      3\n/   \\   /  
\n4     5 6    7\n/\nstruct Node root = new Node(1);\nroot->left = new Node(2);\nroot->left->left = new Node(4);\nroot->left->right = new Node(5);\nroot->right = new Node(3);\nroot->right->left = new Node(6);\nroot->right->right = new Node(7);\nprintLeftAndRightViewIterative(root);\nreturn 0;\n}

Left view and Right view of a binary tree using Recursion

For printing the left node we will recursively call the left part of the tree and print it, and for the right view, we'll recursively call the right part of the tree and print it.

#include<bits/stdc++.h>\nusing namespace std;\nstruct Node{\nint data;\nNode* left;\nNode* right;\nNode(int data){\nthis->data = data;\nleft = right = NULL;\n}\n};
\nvoid printLeftAndRightViewRecursive(Node* root){\nif(root == NULL) return;
\ncout&lt;&lt;root-&gt;data &lt;&lt;\" \";\nprintLeftAndRightViewRecursive(root-&gt;left); // for left view\n//printLeftAndRightViewRecursive(root-&gt;right); //for right view\n
\n}
\nint main() {\n/*\n1\n/    
\n2      3\n/   \\   /  
\n4     5 6    7\n/\nstruct Node root = new Node(1);\nroot->left = new Node(2);\nroot->left->left = new Node(4);\nroot->left->right = new Node(5);\nroot->right = new Node(3);\nroot->right->left = new Node(6);\nroot->right->right = new Node(7);\nprintLeftAndRightViewRecursive(root);\nreturn 0;\n}

\n","title":"Left View and Right View of a Binary Tree","authorDetails":{"name":"studymite","slug":"admin"},"description":"Printing left and right view of a binary tree using iteration and recursion.","slug":"left-view-and-right-view-of-a-binary-tree/","articleId":"636a83417bb1ce5072622b04","bookmarkStatus":{"isBookmarked":false,"bookmarkId":null}}