Invalid escape sequence

error

Invalid escape sequence (valid ones are  \b  \t  \n  \f  \r  \"  \'  \\ )

더블쿼터(")가 들어갈 위치 앞에 백슬래쉬/역슬래쉬(\)
java에서 특수문자 사용시 백슬래쉬/역슬래쉬(\) 입력

Stackoverflow

Whenever you're writing regular expressions in Java, remember to escape the \ characters used in the string that defines the regular expression. In other words, if your regular expression contains one \, then you HAVE to write two \\

https://stackoverflow.com/questions/16178955/invalid-escape-sequence-valid-ones-are-b-t-n-f-r

백준 No.10172