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POCannot find the proper base case for a recursive function to 'generate' matrices?
 

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  1. POCannot find the proper base case for a recursive function to 'generate' matrices?
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    <p>I have a recursive function to generate matrices, called <code>lights</code>.</p> <p>This function is called in <code>light_and_color</code>.</p> <p><code>light_col_permutation</code>, called in <code>lights</code>, gives a vector of vector of vector of int.</p> <p>So, in the loop <code>for(vector&lt;vector&lt;int&gt; &gt; aa:light_col_permutations(rowSums, colSums, colIndex))</code> in the code, <code>aa</code> gives a pair of vector.</p> <p><code>aa[0]</code> is the possible values that could go into the row of the matrix at index <code>colIndex</code>.</p> <p><code>aa[1]</code> is the updated (remaining) <code>rowSums</code> that could be filled in, for unfilled rows after <code>colIndex</code>. This is passed into <code>lights</code> recursively, to fill in the next column.</p> <p>What this function is supposed to do is to find <strong>all</strong> matrices for each of <code>aa</code> in <code>light_col_permutations</code>.</p> <p>With the base case in the code, it only finds one such matrix and quits(<code>return</code>s).</p> <p>How can I generate all of them?</p> <p>The following code is a simplified version, so that you can see the structure of the recursion. Please let me know if there is anything unclear. (the whole program is about 800 lines long, but I will post it if requested)</p> <pre><code>void lights(vector&lt;int&gt;&amp; rowSums, vector&lt;int&gt;&amp; colSums, int colIndex, matrix_c mc) { if(colIndex == mc.r) { mc.print_matrix(); } for(vector&lt;vector&lt;int&gt; &gt; aa:light_col_permutations(rowSums, colSums, colIndex)) { mc.row_assign(colIndex, aa[0]); mc.newRowSum = aa[1]; lights(mc.newRowSum, colSums, colIndex+1, mc); } } void light_and_color(int r, int n, int color, string filename) { matrix_c mc(r, n); //zero matrix of size (r) X (r) //here I get rowSums and colSums, but I omitted them lights(rowSums, colSums, 0, mc); } </code></pre>
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      1. POCannot find the proper base case for a recursive function to 'generate' matrices?
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    1. COAdd more context to your question, please. What are you exactly trying to do?
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