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[Solved] Why the values {1, 1, 0, -1, -1, -1, 0, 1} and {0, 1, 1, 1, 0, -1, -1, -1} were chosen for dx[dir] and dy[dir]? [closed]

January 27, 2023 by Kirat

There are up to 8 directions you can move in from any position on the grid. The dx and dy arrays represent the x and y axis offsets of the adjacent cells. Iterating over the elements pairwise gives you: index dir x y 0 e 1 0 1 se 1 1 2 n 0 1 … Read more

[Solved] C++: Can’t understand this code

October 13, 2022 by Kirat

typedef typename vector<Location>::iterator iterator; This defines a new type alias iterator which maps to vector<Location>::iterator. The typedef itself isn’t actually used in this piece of code though. unordered_map<Location, vector<Location> > edges; This defines an std::unordered_map http://www.cplusplus.com/reference/unordered_map/unordered_map/ edges in which Location (which is the templated type) is the Key value and an std::vector of Locations is … Read more