= LET(V => a.filter交差点b.includes(V))がアレイの交点を返し
LET -difference = a.concat(B).filter(V =>!a.includes(V)||!b.includes(V))が差分アレイ要素を返します
= LET(V => a.filter交差点b.includes(V))がアレイの交点を返し
LET -difference = a.concat(B).filter(V =>!a.includes(V)||!b.includes(V))が差分アレイ要素を返します