#matrices

Solutions This is a classical problem called Flood fill that can be solved in a relatively easy way: look for all pixels in the image that are connected to the start pixel by a path of the target color and changes them to the new color. This algorithm is typically implemented using either recursion or a stack (or queue). This is a recursive implementation example: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 void recursivePaintFill(vector<vector<int>>& image, int r, int c, int color, int newColor) { if (image[r][c] == color) { image[r][c] = newColor; if (r >= 1) { recursivePaintFill(image, r - 1, c, color, newColor); } if (c >= 1) { recursivePaintFill(image, r, c - 1, color, newColor); } if (r + 1 < image. [Read More]

A bunch of villains are waiting in line for being accepted on board of the Queen Anne’s Revenge, docked somewhere in Nassau, to become part of the crew. Every rascal is represented by a number corresponding to the “pieces of eight” they have stolen so far. However, the pirates of the Queen Anne’s Revenge are as crazy as the captain and arrange that line in a spiral: Rascals that make it wrong will walk the plank! [Read More]