What are some examples of memoization in different programming languages?

What are some examples of memoization in different programming languages?

Memoization is a technique used to optimize functions by caching their results. In Python, for example, you can use the functools.lru_cache decorator to memoize function calls. In JavaScript, you can create a memoization function that stores results in an object.

Can you show me a code example in Python?

Sure! Here's a simple example in Python:

from functools import lru_cache

@lru_cache(maxsize=None)
def fibonacci(n):
    if n < 2:
        return n
    return fibonacci(n-1) + fibonacci(n-2)

This code uses memoization to efficiently calculate Fibonacci numbers.

What about in Java?

In Java, you can implement memoization using a HashMap. Here's an example:

import java.util.HashMap;

public class Fibonacci {
    private static HashMap<Integer, Integer> memo = new HashMap<>();

    public static int fibonacci(int n) {
        if (n < 2) return n;
        if (memo.containsKey(n)) return memo.get(n);
        int result = fibonacci(n - 1) + fibonacci(n - 2);
        memo.put(n, result);
        return result;
    }
}

Are there any other languages that use memoization?

Yes, many languages support memoization! For instance, in Ruby, you can use a similar approach with hashes, and in C++, you can use unordered maps to cache results.