Algorithm-DataStructures-Math-SQL/Algorithm/DynamicProgramming/DynamicProgramming(Andrei).js at main · myoshi2891/Algorithm-DataStructures-Math-SQL · GitHub

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// function memoizedAddTo80() {
// 	let cache = {};

// 	return function (n) {
// 		if (n in cache) {
// 			return cache[n];
// 		} else {
// 			console.log("long time");
// 			cache[n] = n + 80;
// 			return cache[n];
// 		}
// 	};
// }

// const memoized = memoizedAddTo80();
// console.log("1", memoized(5));
// console.log("2", memoized(5));

let calc = 0;
function fibonacci(n) {
    calc++;
    if (n < 2) {
        return n;
    }
    return fibonacci(n - 1) + fibonacci(n - 2);
}

function fibonacciMaster() {
    let cache = {};
    return function fib(n) {
        calc++;
        if (n in cache) {
            return cache[n];
        } else {
            if (n < 2) {
                return n;
            } else {
                cache[n] = fib(n - 1) + fib(n - 2);
                return cache[n];
            }
        }
    };
}

function fibonacciMaster2(n) {
    let answer = [0, 1];
    for (let i = 2; i <= n; i++) {
        answer.push(answer[i - 2] + answer[i - 1]);
    }
    return answer.pop();
}

const fasterFib = fibonacciMaster();

console.log(fasterFib(10));
console.log(calc); // 46368
console.log(fibonacciMaster2(10));