60 lines
1.5 KiB
JavaScript
60 lines
1.5 KiB
JavaScript
/**
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* Fibonacci implementations - CommonJS module
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* Intentionally inefficient for optimization testing.
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*/
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/**
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* Calculate the nth Fibonacci number using naive recursion.
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* This is intentionally slow to demonstrate optimization potential.
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* @param {number} n - The index of the Fibonacci number to calculate
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* @returns {number} The nth Fibonacci number
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*/
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function fibonacci(n) {
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if (n <= 1) {
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return n;
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}
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return fibonacci(n - 1) + fibonacci(n - 2);
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}
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/**
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* Check if a number is a Fibonacci number.
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* @param {number} num - The number to check
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* @returns {boolean} True if num is a Fibonacci number
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*/
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function isFibonacci(num) {
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// A number is Fibonacci if one of (5*n*n + 4) or (5*n*n - 4) is a perfect square
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const check1 = 5 * num * num + 4;
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const check2 = 5 * num * num - 4;
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return isPerfectSquare(check1) || isPerfectSquare(check2);
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}
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/**
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* Check if a number is a perfect square.
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* @param {number} n - The number to check
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* @returns {boolean} True if n is a perfect square
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*/
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function isPerfectSquare(n) {
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const sqrt = Math.sqrt(n);
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return sqrt === Math.floor(sqrt);
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}
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/**
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* Generate an array of Fibonacci numbers up to n.
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* @param {number} n - The number of Fibonacci numbers to generate
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* @returns {number[]} Array of Fibonacci numbers
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*/
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function fibonacciSequence(n) {
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const result = [];
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for (let i = 0; i < n; i++) {
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result.push(fibonacci(i));
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}
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return result;
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}
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// CommonJS exports
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module.exports = {
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fibonacci,
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isFibonacci,
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isPerfectSquare,
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fibonacciSequence,
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};
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