Contest Link:
https://codeforces.com/group/jdIz2fe1Or/contests
Problems Solved:
1. Valid BFS? (Problem I)
Solution: https://ideone.com/3s0KVN
2. Police Stations (Problem J)
Solution: https://ideone.com/YBxr2R
3. Three States (Problem O)
Solution: https://ideone.com/RxLUIn
4. Chamber of Secrets (Problem P)
Solution: https://ideone.com/9ou3UP
5. Getting Zero (Problem D)
Solution: https://ideone.com/NaQlT0
