const a = { familyName: '織田', firstName: '吉法師', address: '尾張', sex: '男', details: { character: { favoriteTactics: '奇襲', favoriteWord: '天下布武', favoritePlace: '京' }, ownedCastle: [ '清洲城' ] } }; const b = { familyName: '織田', firstName: '信長', details: { character: { favoriteTactics: '鉄砲活用' }, ownedCastle: [ '岐阜城', '安土城' ] } };