syntax error but its from HP Prime Exercises..what up with that?

[tom234]

The error is in ""M; dont know why?
anyone know why?


EXPORT CESAR()
BEGIN
local n;
LOCAL S,M,K;
””M;
//The user is asked to enter the encrypted word
INPUT(n,”Insert in quotation marks”,”Encrypted word”);
SIZE(n)S;
FOR K FROM 1 TO S DO
//This time we shift by 3 letters backwards
M+CHAR(ASC(MID(n,K,1))-3)M;
END;
PRINT(M);
END;