I have been trying to solve a question but I have a bug in my code which I need to fix. I also have files with inputs and corresponding outputs for this question. However the problem is that the input files are extremely big (about 3.5MB). Therefore, I cannot run it on my laptop as I get a segfault (I am certain it is because of stack overflow when I am doing dfs as I have done many tests). And I cannot run it on any online compiler, including codeforces, because the input file is too big. Most websites only allow input as big as a few hundred KB.

So my question is — How am i supposed to run my code with this input? The online grader where I found this problem only tells me if I got a testcase right or wrong or TLE, MLE, etc. It doesn't tell me anything as to the difference between expected and my output. So what should i do?

Note: I can't really find any smaller testcases either and every testcase that I make myself seems to work.