Javascript找到数组的第n个元素

Question

I have looked at this code for a few hours and cannot understand how it works and how it gives an answer of 1.

If someone could explain this to me in easy to understand terms (I am new to Javascript) I would really appreciate it. The code is below. Thank you:

var array = [1, 3, 2, 9];
var one = -Infinity;
var two = -Infinity;
var three = -Infinity;

for (i = 0; i < array.length; i++) {

    if (array[i] > one) {
        three = two;
        two = one;
        one = array[i];
    }
}

console.log(three);

Answer 1

Just think about the values in the loop and you will know why the last value of "three" is 1. These are the values at the end of each iteration:

|---------------------|------------------|---------------------|------------------|
|         i=0         |        i=1       |         i=2         |        i=3       |
|     three=-inf      |     three=-inf   |     three=-inf      |     three=1      | 
|     two=-inf        |     two=1        |     two=1           |     two=3        | 
|     one=1           |     one=3        |     one=3           |     one=9        | 
|---------------------|------------------|---------------------|------------------|