Preorder Binary Tree

Posted: 3 Aug, 2017
Difficulty: Easy

PROBLEM STATEMENT

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You are given the root node of a binary tree.Print its preorder traversal.

Input Format:
The first and the only line of input will contain the node data, all separated by a single space. Since -1 is used as an indication whether the left or right node data exist for root, it will not be a part of the node data.
Output Format:
The only line of output prints the preorder traversal of the given binary tree.
Constraints:
1 <= N <= 10^6
Where N is the total number of nodes in the binary tree.

Time Limit: 1 sec
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