2020-2021:teams:running_chicken:counttriangleonug [CVBB ACM Team]

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2020-2021:teams:running_chicken:counttriangleonug [CVBB ACM Team]

2020-2021:teams:running_chicken:counttriangleonug

去掉图中的自环，新图的邻接矩阵的三次幂的迹除以6

因为不存在自环，所以从i到i的三次路径一定经过两个不同的点j和k，i、j、k构成三角形。但每个ijk对迹的贡献是6（ijk的所有排列），故除以6

2020-2021/teams/running_chicken/counttriangleonug.txt · 最后更改: 2020/08/26 17:44 由 yyxzhj