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PORecursive member function can't access its own variables
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  1. PORecursive member function can't access its own variables
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    copied!<p>I start with the top node of a tree 5 layers deep, and recursively call getvalue() on each one. Each node is linked to two nodes on the next layer. I'm pretty sure that this is not my issue since I double checked the algorithm on paper. Once I get to layer 3, however, it gives me a segmentation fault. With valgrind, I figured out that it was raised when I tried to print the class variable <code>oper</code>. I have no idea where to go with this, so your help is greatly appreciated. This is the code:</p> <pre><code>class Node { public: vector&lt;Node&gt; children; long constval; char oper; void setconst(); Node(); void copy(const Node*); int getvalue(); private: int mult(int,int); int div(int,int); int add(int,int); int sub(int,int); }; Node::Node() { bool c = false; vector&lt;char&gt; operations; operations.push_back('m'); operations.push_back('a'); operations.push_back('s'); operations.push_back('d'); operations.push_back('c'); constval = rand(); int randnum = rand() % 5; cout &lt;&lt; randnum &lt;&lt; "\n"; oper = operations[randnum]; } int Node::getvalue() { cout &lt;&lt; oper &lt;&lt; '\n'; if (oper == 'm') { return Node::mult(children[0].getvalue(), children[1].getvalue()); } else if (oper == 'd') { return Node::div(children[0].getvalue(), children[1].getvalue()); } else if (oper == 'a') { return Node::add(children[0].getvalue(), children[1].getvalue()); } else if (oper == 's') { return Node::sub(children[0].getvalue(), children[1].getvalue()); } else if (oper == 'c') { return constval; } } </code></pre> <p>EDIT: Here is my initializing algo:</p> <pre><code>class Individual { public: vector&lt; vector&lt;Node&gt; &gt; nodes; vector&lt; vector&lt;Node&gt; &gt; getrand(); void replace(vector&lt; vector&lt;Node&gt; &gt;); void mutate(double); double run(); Individual(); }; Individual::Individual() { nodes.resize(5); nodes[0].resize(1); int size = 2; for(int i = 1; i &lt; 5; i++) { nodes[i].resize(size); size = size * 2; } vector&lt;char&gt; operations; operations.push_back('a'); operations.push_back('s'); operations.push_back('d'); operations.push_back('m'); nodes[0][0].oper = operations[rand() % 4]; for(int x = 0; x &lt; nodes[4].size(); x++) { nodes[4][x].setconst(); } for(int i = 0; i &lt; 4; i++) { for(int x = 0; x &lt; nodes[i].size(); x++) { nodes[i][x].children.push_back(nodes[i+1][x*2]); nodes[i][x].children.push_back(nodes[i+1][x*2+1]); } } } </code></pre>
 

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