ligo/test/contracts/max_in_list.tz

parameter (list int);
storage unit;
return (option int);
code {CAR; DIP{NONE int};
      LAMBDA
        (pair int (option int))
        (option int)
        {DUP; DUP; CAR; SWAP; CDR;
         IF_NONE {DIP{DROP}; SOME} {CMPGT; IF {CDR} {CAR; SOME}}};
      REDUCE; UNIT; SWAP; PAIR};