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Construct a binary tree of size **N** using two given arrays **pre[]** and **preLN[]**. Array **pre[]** represents preorder traversal of a binary tree. Array **preLN[]** has only two possible values **L** and **N**. The value **L** in **preLN[]** indicates that the corresponding node in Binary Tree is a leaf node and value N indicates that the corresponding node is a non-leaf node.

**Note:** Every node in the binary tree has either 0 or 2 children.

**Example 1:**

Input :N = 5 pre[] = {10, 30, 20, 5, 15} preLN[] = {N, N, L, L, L}Output:10 / \ 30 15 / \ 20 5

**Your Task: **

You dont need to read input or print anything. Complete the function **constructTree()** which takes N, pre[] and preLN[] as input parameters and returns the root node of the constructed binary tree.

**Note:** The output generated by the compiler will contain the inorder traversal of the created binary tree.

**Expected Time Complexity:** O(N)

**Expected Auxiliary Space: **O(N)

**Constraints:**

1 ≤ N ≤ 10^{4}

1 ≤ pre[i] ≤ 10^{7}

preLN[i]: {'N', 'L'}

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Construct Tree from Preorder Traversal

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