CREATE TABLE table_name_21 (total INTEGER, snatch VARCHAR(255), event VARCHAR(255), clean_ VARCHAR(255), _jerk VARCHAR(255))
What is the lowest total that had less than 170 snatches, 56 kg events and less than 145 clean & jerk?
    
SQL: SELECT MIN(total) FROM table_name_21 WHERE snatch < 170 AND event = "56 kg" AND clean_ & _jerk < 145