Problem:
Score : 400 points

Problem Statement

There are N empty boxes arranged in a row from left to right.
The integer i is written on the i-th box from the left (1 \leq i \leq N).

For each of these boxes, Snuke can choose either to put a ball in it or to put nothing in it.

We say a set of choices to put a ball or not in the boxes is good when the following condition is satisfied:

For every integer i between 1 and N (inclusive), the total number of balls contained in the boxes with multiples of i written on them is congruent to a_i modulo 2.

Does there exist a good set of choices? If the answer is yes, find one good set of choices.

Constraints

All values in input are integers.

1 \leq N \leq 2 \times 10^5

a_i is 0 or 1.

Input

Input is given from Standard Input in the following format:

N
a_1 a_2 ... a_N

Output

If a good set of choices does not exist, print -1.

If a good set of choices exists, print one such set of choices in the following format:

M
b_1 b_2 ... b_M

where M denotes the number of boxes that will contain a ball, and b_1,\ b_2,\ ...,\ b_M are the integers written on these boxes, in any order.

Sample Input 1

3
1 0 0

Sample Output 1

1
1

Consider putting a ball only in the box with 1 written on it.

There are three boxes with multiples of 1 written on them: the boxes with 1, 2, and 3. The total number of balls contained in these boxes is 1.

There is only one box with a multiple of 2 written on it: the box with 2. The total number of balls contained in these boxes is 0.

There is only one box with a multiple of 3 written on it: the box with 3. The total number of balls contained in these boxes is 0.

Thus, the condition is satisfied, so this set of choices is good.

Sample Input 2

5
0 0 0 0 0

Sample Output 2

0

Putting nothing in the boxes can be a good set of choices.

Solution in JavaScript (node.js v5.12) (judge verdict: Wrong Answer)

function main(input){
  input = input.split("\n");
  var n = parseInt(input[0]);

  var a = [];

  for (var i = 0; i < n; i++) {
    a[i] = parseInt(input[1].split(" ")[i]);
  }

  //console.log(a);


  var tama = [];
  var answer = [];
  var hanbun = Math.floor(n / 2);

// tamaは0が値なしになる
  for (var i = n; i > hanbun; i--){
    tama[i] = a[i-1];
    answer.push(i);
  }

  for (var i = hanbun; i>0; i--){
    var hantei = a[i-1];
    for (var j = 2; i*j <= n; j++){
      hantei += tama[i*j];
    }
    tama[i] = hantei%2;
    if (tama[i] == 1) {
      answer.push(i);
    }
  }

//console.log(tama);
//console.log(answer);

console.log(answer.length);
for (var i = 0; i < answer.length; i++) {
  process.stdout.write(answer[i]+" ");
}



}
 
 
main(require('fs').readFileSync('/dev/stdin', 'utf8'));