fetch -o - http://eval.dan.co.jp/friends/2026/11/08/4f98798cae76203aa9cc0706272f3a49470626d6b4487862bede34ef3037529b | sed '/lambda R:/s/(P[[]0[]],)/(P[-1],)/;/lambda R:/s/sm(P[[]i[]],/sm(P[-1-i],)/' | sh