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PORecursive floodFill function? C++
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copied!<p>So recursion is not my strong point, and I have been challenged to make a recursive floodFill function that fills a vector of a vector of ints with 1's if the value is zero. My code keeps segfaulting for reasons beyond me. Perhaps my code will make that sound more clear. </p> <p><strong>This is the grid to be flood filled:</strong></p> <pre><code>vector<vector<int> > grid_; </code></pre> <p>It belongs to an object I created called "Grid" that is basically a set of functions to help manipulate the vectors. The grid's values are initialized to all zeros. </p> <p><strong>This is my flood fill function:</strong></p> <pre><code>void floodFill(int x, int y, Grid & G) { if (G.getValue(x,y)) { G.setValue(x,y,1); if(x < G.getColumns()-1 && x >= 0 && y < G.getRows()-1 && y >= 0) floodFill(x+1,y,G); if(x < G.getColumns()-1 && x >= 0 && y < G.getRows()-1 && y >= 0) floodFill(x,y+1,G); if(x < G.getColumns()-1 && x >= 0 && y < G.getRows()-1 && y >= 0) floodFill(x-1,y,G); if(x < G.getColumns()-1 && x >= 0 && y < G.getRows()-1 && y >= 0) floodFill(x,y-1,G); } } </code></pre> <p>The intention here is to have the function check if a point's value is zero, and if it is, change it to one. Then it should check the one above it for the same. It does this until it either finds a 1 or hits the end of the vector. Then it tries another direction and keeps going until the same conditions as above and so on and so forth until its flood filled. </p> <p>Can anyone help me fix this? Maybe tell me whats wrong?</p> <p>Thanks!</p>

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