C++ EULER特徵數定理與UnionFind解Leetcode959 Regions Cut By Slashes

EULER特徵數定理與UnionFind解Leetcode959 Regions Cut By Slashes

EULER特徵數定理:平面連通圖有V-E+F

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 Theorem of Euler-Characteristic: for a connected planar graph,

V-E+F=2 ,

outside of the graph there is  a face

[codes on Leetcode]https://leetcode.com/problems/regions-cut-by-slashes/solutions/5614770/unionfind-dfs-euler-theorem-v-e-f-2-beats-100/

[Tree & Graph Playlist]https://www.youtube.com/watch?v=9Lx7yr-tmfI&list=PLYRlUBnWnd5Kt0-3un43cwY6yT_il8NWe

[Leetcode程式 playlist]https://www.youtube.com/watch?v=527BNZYm6aE&list=PLYRlUBnWnd5IdDHk2BjqXwesydU17z_xk&index=3