BCAlgTori for GAP 4

See

BCAlgTori-2022.01.27.pdf or
http://mathweb.sc.niigata-u.ac.jp/~hoshi/Algorithm/BCAlgTori/BCAlgTori-2022.01.27.pdf or
https://www.math.kyoto-u.ac.jp/~yamasaki/Algorithm/BCAlgTori/BCAlgTori-2022.01.27.pdf

See the following for further explanations:

crystcat.pdf or
http://mathweb.sc.niigata-u.ac.jp/~hoshi/Algorithm/BCAlgTori/crystcat.html or
https://www.math.kyoto-u.ac.jp/~yamasaki/Algorithm/BCAlgTori/crystcat.html

FlabbyResolutionBC.pdf or
http://mathweb.sc.niigata-u.ac.jp/~hoshi/Algorithm/BCAlgTori/FlabbyResolutionBC.html or
https://www.math.kyoto-u.ac.jp/~yamasaki/Algorithm/BCAlgTori/FlabbyResolutionBC.html