this story is based on the Chinese Remainder Theorem (CRT) (within range ),
a theorem of number theory. The CRT states that if one knows the remainders of the division of an integer n by several integers,
then one can determine uniquely the remainder of the division of n by the product of these integers, under certain conditions.
in here we should found suitable answers between range with run this code and enter in answer
after answer was correct 6 parmeters n1 and n2 and n3 and c1 and c2 and c3 are given to us that are math behide correct answer athat is rsa Wieners Attack
full code for both part is here:https://cybersecctf.github.io/blog/?q=sunzisperfectmathclass%20down

Original writeup (https://cybersecctf.github.io/blog/?q=sunzisperfectmathclass%20down).