Topcoder SRM Challenge phase: how to find bugs in code

I have participated over 150 SRMs (Single Round Algorithmic Match) in Topcoder. An important phase during a SRM is to find bugs in other coders code and challenge them with a critical input that you define or create. So far I challenged 68 times in my topcoder history with a success rate of 53%. Here I will point out some strategies to successfully challenge anyone’s code in Topcoder (and Codeforces) and earn some guaranteed points before system test. After pointing out each strategy, I will try to provide links for challenges where I created inputs that failed other’s code.

Strategies to find bugs in other’s code

• The common strategy is to find some corner cases for the coding problem and see if other contestants in the challenge room handled those corner cases. My successful challenges on this criteria below:

— https://community.topcoder.com/stat?c=problem_solution&rm=333217&rd=17723&pm=15736&cr=40987291#defenses

— https://community.topcoder.com/stat?c=problem_solution&rm=330870&rd=17055&pm=14783&cr=40626413#defenses

— https://community.topcoder.com/stat?c=problem_solution&rm=330151&rd=16883&pm=14592&cr=40462146#defenses

• See if boolean expressions are written correctly. for example

x>u vs x≥u,

(a>b) && (c>d) vs (a>b) || (c>d).

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