Implement HashMap put/get with Optimal Rehash Strategy

Implement a HashMap with put/get and an Optimal Rehash Strategy Implement a simplified HashMap supporting: put(key, value) get(key) (return null/None if missing) When the load factor exceeds a threshold, the map must resize. Additional requirement: Discuss/implement a strategy to avoid rehashing all entries at once during resize (e.g., incremental rehash / gradual migration) to reduce worst-case latency. Must cover Collision handling (chaining/open addressing) Resize trigger Incremental rehash data structures and migration steps Lookup logic during migration (old + new tables coexist) Scale Support ~1e5 keys with amortized performance. Example tests Basic put/get Update existing key After resize, all keys still retrievable Mid-migration correctness Performance doesn’t degrade to O(n) Example Input put(1,10); get(1) Output 10