fibonnaci.js

// Population de lapins : [1, 1, 2, 3, 5, 8, 13 21 34 55 89 <3 <3 !
// fibonnaci(0) = 1
// fibonnaci(1) = 1
// fibonnaci(2) = 2
// fibonnaci(3) = 3
// fibonnaci(4) = 5
// fibonnaci(10) = 89

/**************** BAD ******************/

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

/**************** GOOD *****************/

let solutions = [1, 1];

let fibonnaci = function(n) {
	if (solutions[n]) {
	   return solutions[n];
	}
	solutions[n] = fibonnaci(n - 1) + fibonnaci(n - 2);
	return solutions[n];
};

// TEST:

console.log("fibonnaci(1000) = " + fibonnaci(1000));