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			27 lines
		
	
	
		
			824 B
		
	
	
	
		
			HTML
		
	
	
	
	
	
			
		
		
	
	
			27 lines
		
	
	
		
			824 B
		
	
	
	
		
			HTML
		
	
	
	
	
	
<p>You are given a binary tree in which each node contains an integer value (which might be positive or negative). Design an algorithm to count the number of paths that sum to a given value. The path does not need to start or end at the root or a leaf, but it must go downwards (traveling only from parent nodes to child nodes).</p>
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<p><strong>Example:</strong><br />
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Given the following tree and  <code>sum = 22,</code></p>
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<pre>
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              5
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             / \
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            4   8
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           /   / \
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          11  13  4
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         /  \    / \
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        7    2  5   1
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</pre>
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<p>Output:</p>
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<pre>
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3
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<strong>Explanation: </strong>Paths that have sum 22 are: [5,4,11,2], [5,8,4,5], [4,11,7]</pre>
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<p>Note:</p>
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<ul>
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	<li><code>node number <= 10000</code></li>
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</ul>
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