# File warshall.rb, line 204 def addPaar!(x,y) @basis.add(x) @basis.add(y) @nach[x] = Menge.new([y]) + @nach[x] @nach[y] = Menge.new([]) if @nach[y]==nil @vor[y] = Menge.new([x]) + @vor[y] @vor[x] = Menge.new([]) if @vor[x]==nil return self end