NiNi's Den

# NiNi's Den

problem 3 Given an integer (not necessary a decimal number) with n digits, we want to remove $m (\le n)$ digits from this number such that the resulting number is as large as possibe. Design an $O(n)$ time algorithm to solve it. problem 4 Given a 2-dimensional nn array (or matrix) of 0/1 inte...

Written in English.

2017::HITCON-Quals::Sakura::English

Ask to input 400 chars, then take it as a 20*20 arry
Next the binary run a function to verify the array
If the verification were success, it would give you the SHA256 hash of you input, which is flag

Let’s take a look at the function I mentioned
There are 150 while loops in this function
Before loops, it initialize lots of variables
Those loops are all similar to each:

2017::HITCON-qual::Sakura