Add hack of Connected Components of Complement Graph

[OmeletWithoutEgg]

the wrong solution, also see random_kruskal.cpp.

This solution randomly selects a pair of point as an edge, and merge them if the edge is in the complement graph. Repeat this process for 10^7 times, you can pass all the previous testcases.

I added a testcase that there is an edge you must merge, and the probability of choosing it is about 1/N^2, so that this solution will fail with quite high probability.

ref: https://judge.yosupo.jp/hack/154

[maspypy]

Thank you very much.

It seems that there's an error in sol/random_kruskal.cpp. Additionally, on Library Checker, there are environment-dependent issues, so we generally avoid using random uniform_int_distribution. Therefore, I apologize, but I plan to merge after deleting the sol you created.