CSES - limited universe
  • Time limit: 2.10 s
  • Memory limit: 512 MB
Create a data structure that beats std::unordered set for a limited universe size.

Note that CSES doesn't support command line parameters, so either hard code a limit of 10^6 into your code, or just use the limit of 2^31 - 1 as long as you use less than 512 MB of space.