How can I implement an MRU cache in Python?

How can I implement an MRU cache in Python?

To implement an MRU (Most Recently Used) cache in Python, you can use a dictionary to store the cache items and a list to track the order of usage.

Can you provide a sample code for that?

Sure! Here's a simple implementation:

class MRUCache:
    def __init__(self, capacity):
        self.cache = {}
        self.order = []
        self.capacity = capacity

    def get(self, key):
        if key in self.cache:
            self.order.remove(key)
            self.order.append(key)
            return self.cache[key]
        return -1

    def put(self, key, value):
        if key in self.cache:
            self.order.remove(key)
        elif len(self.cache) >= self.capacity:
            oldest = self.order.pop(0)
            del self.cache[oldest]
        self.cache[key] = value
        self.order.append(key)

How does this code handle the cache size?

The cache size is managed by checking the length of the cache dictionary against the capacity. If the cache exceeds the capacity, the least recently used item (the first item in the order list) is removed.