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<h1>1053. Path of Equal Weight (30)</h1>
<div id="problemContent">
<p>Given a non-empty tree with root R, and with weight W<sub>i</sub> assigned to each tree node T<sub>i</sub>. The <b>weight of a path from R to L</b> is defined to be the sum of the weights of all the nodes along the path from R to any leaf node L.</p>
<p>Now given any weighted tree, you are supposed to find all the paths with their weights equal to a given number. For example, let's consider the tree showed in Figure 1: for each node, the upper number is the node ID which is a two-digit number, and the lower number is the weight of that node. Suppose that the given number is 24, then there exists 4 different paths which have the same given weight: {10 5 2 7}, {10 4 10}, {10 3 3 6 2} and {10 3 3 6 2}, which correspond to the red edges in Figure 1.
</p>
<center><img src="http://nos.patest.cn/5b_mj58f84v11w.jpg"/><br/>Figure 1</center>
<p><b>
Input Specification:
</b></p>
<p>Each input file contains one test case. Each case starts with a line containing 0 &lt; N &lt;= 100, the number of nodes in a tree, M (&lt; N), the number of non-leaf nodes, and 0 &lt; S &lt; 2<sup>30</sup>, the given weight number. The next line contains N positive numbers where W<sub>i</sub> (&amp;lt1000;) corresponds to the tree node T<sub>i</sub>. Then M lines follow, each in the format:</p>
<pre>
ID K ID[1] ID[2] ... ID[K]
</pre>
<p>where ID is a two-digit number representing a given non-leaf node, K is the number of its children, followed by a sequence of two-digit ID's of its children. For the sake of simplicity, let us fix the root ID to be 00.</p>
<p><b>
Output Specification:
</b></p>
<p>For each test case, print all the paths with weight S in <b>non-increasing</b> order. Each path occupies a line with printed weights from the root to the leaf in order. All the numbers must be separated by a space with no extra space at the end of the line.
</p>
<p>Note: sequence {A<sub>1</sub>, A<sub>2</sub>, ..., A<sub>n</sub>} is said to be <b>greater than</b> sequence {B<sub>1</sub>, B<sub>2</sub>, ..., B<sub>m</sub>} if there exists 1 &lt;= k &lt; min{n, m} such that A<sub>i</sub> = B<sub>i</sub> for i=1, ... k, and A<sub>k+1</sub> &gt; B<sub>k+1</sub>.</p>
<b>Sample Input:</b><pre>
20 9 24
10 2 4 3 5 10 2 18 9 7 2 2 1 3 12 1 8 6 2 2
00 4 01 02 03 04
02 1 05
04 2 06 07
03 3 11 12 13
06 1 09
07 2 08 10
16 1 15
13 3 14 16 17
17 2 18 19
</pre>
<b>Sample Output:</b><pre>
10 5 2 7
10 4 10
10 3 3 6 2
10 3 3 6 2
</pre>
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