3 methods for get fibonacci list element

fibonacci.js

#!/usr/bin/env node
/*
  use node fibonacci num in terminal to get fibonacci list element
*/
var fibonacci1 = function(n) {
    if (n < 1) {
        return 0;
    } else if (n === 1 || n ===2) {
        return 1;
    } else if (n > 2) {
        return fibonacci1(n - 1) + fibonacci1(n - 2);
    }
};

var fibonacci2 = function(n) {
    var ret = 0,
        f0 = 0,
        f1 = 1,
        i = 0;
    for(; i <= n; i++) {
        ret += f0;
        f0 = f1;
        f1 = ret;
    }
    return ret;
};

var fibonacci3 = function(n) {
    var phi = (1 + Math.sqrt(5)) / 2;
    return Math.round((Math.pow(phi, n) - Math.pow(1 - phi, n)) / Math.sqrt(5));
};

var num = process.argv[2] || 1;
var time = process.hrtime();
console.log(fibonacci1(num));
console.log(process.hrtime(time)[0] + 's');
time = process.hrtime();
console.log(fibonacci2(num));
console.log(process.hrtime(time)[0] + 's');
time = process.hrtime();
console.log(fibonacci3(num));
console.log(process.hrtime(time)[0] + 's');