fibonacci

by alex_o

JavaScript

function fibonacci(n){
	var start = Date.now();
	var res = [0,1], i;
  
  for(i=2;i<n+1;i++){
  	res[i] = res[i-2] + res[i-1];
  }  
  console.log('fibonacci function ran '+ (Date.now() - start));
  return res[n];
}

function fibonacciRecursive(n){
	if(n<=1) return n;
  else return fibonacciRecursive(n-2)+ fibonacciRecursive(n-1);
}

function fibonacciRecursiveWithTiming(n){
 var start = Date.now();
 var res = fibonacciRecursive(n);
 console.log('recursive ran ' + (Date.now()- start));
 return res;
}


function runFibonacci(){
	var n = prompt('Enter number');
  
  alert('Result is ' + "\n ususal "+ fibonacci(n) + "\n recursive "+fibonacciRecursiveWithTiming(n));  
}

runFibonacci();