Lazy-loaded Image

Imagine you want to fetch a list of posts along with their authors:

$posts = Post::all();

foreach ($posts as $post) {
    echo $post->author->name;
}

import React, { useMemo } from 'react';

function Fibonacci({ num }) {
  const fib = useMemo(() => {
    const calculateFibonacci = (n) => {
      if (n <= 1) return 1;
      return calculateFibonacci(n - 1) + calculateFibonacci(n - 2);
    };
    return calculateFibonacci(num);
  }, [num]);

  return <div>Fibonacci of {num} is {fib}</div>;
}

This ensures that the Fibonacci number is only recalculated when num changes, improving performance.