推送后未定义的数组

Question

I'm trying to obtain to sort an array of mountain from the tallest to the smallest but when trying to print, I get

TypeError: mountainArray[i] is undefined

I think i'm not missing any step for the solution but I get undefined.

Thanks in advance

Code below:

 var position; var height; function Mountain(position, height) { this.position = position; this.height = height; } function sortMountain(a, b) { return b.height - a.height; } var mountainArray = []; // game loop while (true) { for (var i = 0; i < 8; i++) { var mountainH = parseInt(readline()); // represents the height of one mountain, from 9 to 0. mountainArray.push(Mountain(i, mountainH)); mountainArray.sort(sortMountain); } for (var i = 0; i < 8; i++) { print(mountainArray[i].position); } } 

Answer 1

The way you have your class written:

function Mountain(position, height) {
  this.position = position;
  this.height = height;
}

You need to use the new keyword when you push:

while (true) {
  for (var i = 0; i < 8; i++) {
    var mountainH = parseInt(readline()); // represents the height of one mountain, from 9 to 0.

    mountainArray.push(new Mountain(i, mountainH)); // HERE
    mountainArray.sort(sortMountain);


  }
  for (var i = 0; i < 8; i++) {
    print(mountainArray[i].position);
  }
}

as pointed out in the comments, you should only sort once, no need to do it every time in your loop.