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38 lines
1.8 KiB
HTML
38 lines
1.8 KiB
HTML
<!DOCTYPE html>
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<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
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<h1>1099. Build A Binary Search Tree (30)</h1>
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<div id="problemContent">
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<p>A Binary Search Tree (BST) is recursively defined as a binary tree which has the following properties:</p>
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<li>The left subtree of a node contains only nodes with keys less than the node's key.
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<li>The right subtree of a node contains only nodes with keys greater than or equal to the node's key.
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<li>Both the left and right subtrees must also be binary search trees.
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<p>Given the structure of a binary tree and a sequence of distinct integer keys, there is only one way to fill these keys into the tree so that the resulting tree satisfies the definition of a BST. You are supposed to output the level order traversal sequence of that tree. The sample is illustrated by Figure 1 and 2.
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</p>
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<center><img src="http://nos.patest.cn/h8_nkqjeu5lglo.jpg"/></center>
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<p><b>
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Input Specification:
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</b></p>
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<p>Each input file contains one test case. For each case, the first line gives a positive integer N (<=100) which is the total number of nodes in the tree. The next N lines each contains the left and the right children of a node in the format "left_index right_index", provided that the nodes are numbered from 0 to N-1, and 0 is always the root. If one child is missing, then -1 will represent the NULL child pointer. Finally N distinct integer keys are given in the last line.</p>
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<p><b>
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Output Specification:
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</b></p>
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<p>For each test case, print in one line the level order traversal sequence of that tree. All the numbers must be separated by a space, with no extra space at the end of the line.
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</p>
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<b>Sample Input:</b><pre>
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9
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1 6
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2 3
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-1 -1
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-1 4
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5 -1
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-1 -1
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7 -1
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-1 8
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-1 -1
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73 45 11 58 82 25 67 38 42
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</pre>
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<b>Sample Output:</b><pre>
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58 25 82 11 38 67 45 73 42
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</pre>
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</li></li></li></div> |