For thread safe, LRU_Cache is implemented as below. What is the problem of the following piece of code? Please fix the problem with minimum change. public class LRU_cache_tsafe extends LRU_cache { @Override public V put(K key, V value) { synchronized(this) { super.put(key, value); } return value; } public V get1(K key) { synchronized(this) { V value = super.get(key); } return value; } } Bonus: What is the problem of this implementation? Show the better way to implement put() and get().