My high school math teacher went crazy on me when I withdrew from the math olympiad prep class due to scheduling conflicts with assembler language class in my f

My high school math teacher went crazy on me when I withdrew from the math olympiad prep class due to scheduling conflicts with assembler language class in my first year and then did everything possible for me to fail over the next 4 years. Not sure how would that teacher bear hearing I made it to top schools despite their best efforts...