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 C++14 (GCC 5.4.1) (judge verdict: Wrong Answer)

/* Aa^~ kokoro ga pyonpyon suru n jaa^~
// ZZZXXkXkkkZ!``` ``` ``` ``` ``` ``` ``` ``` ``` ``` ``` ```?Wfpppbpbbpbbpbbbkbkk
// ppbbbpbbpVr`` `` ` ` ` ` ```` `` ` ` ``  ` ` ` ` ` ` ` ` `  dppbbkkkkkkkkkkqkqkk
// HkqqqqqkkWr`` ` ` ``` ``` `?G, ` ` ``.JC!```` ` ` `` `` ````(Wpbkkkkkkkkqkkkkkqk
// mmmmmqqqqpr` `` `` ```````.+zT=`` `` 7TO-.```````` `` `` ```(yppbkkkkkkkkkkkkkkk
// ggmgmmqqqH$ ``````````....````` `  ````````.`````` `` ``````.yfpppbbbbkkkkqqqqqH
// gmmmmmqqqkW<```` `````...`````  .,.`  ````....````` ``````` (Wbqqmgmmgmggggggggg
// qmmmqqqqkkWk.``````````````````` ;:<`` `````.`````````````-_<-?WHHqmmmmmmgmmgggg
// @@@@@@@gggHH6- ``````````````` `` _ `` ```````````````` ._~~_.`-?Wkqmmmmmmmggg@g
// @@@@g@gggHY~.-<_- `````````````````````````````````` ._~~(<-``.`.(WHqqqmmggggmmm
// @@g@gggHH=.`..._<-___..```````````````````````. .-_~~~_(!``-.``.`` OHHWUWHmqHWXW
// gggggmqK1.``..~.. _<<+-(____..  ````````  ..__~~_((<<!.`.``` .``.`` j0C1XUHmHIdW
// ggmmqH0!,_``.>`````` _<<;<v<<<++((((((((((<<<<<<~_. (-.``~``.>..```  jOuWHHqHIdH
// gmmqkW!`(_ J>`    `` ` _~<`_~~~~<<<<<<<~~__````````` ?1. ._`(__```    zXWHg@HkXH
// gHHWS{``(lJ<!``.``.```(:+>`._`````.` <..`` - ``. `   _ ?&._.I`_`````` .XyVfppppW
// HHHSv``.(X:_..... _..(;+<!.(<..-.....-.-_..+_`..<.`.`..`_IJd}  .`..````jqg@@@@@@
// XHWZ{..<Jk~!.`.. (<.-(+>(_.(1.(_..`.`.`.<_.+<_..<<-..._..-zy>.`_`...```.WH@HHHHH
// bkWt~.-jCz(_..`.(+<.(;< ._-<=_(<_..-....(_.<1<..(<<.`._..-JUS-._.`...```dHmH9VUH
// WUUO..(f.(c...__+z<-(+~` _-+<_(><..__.`.(<._.z_.(1;_..__.(C(zT-(..`...``(WHR<+Xk
// kkkk._(_.->..._(z;:_><.._>_+_<(1>_._<...(v<<.(<.(+z<..-_(Z~_<_j+_..`...`(WHKz1ZW
// @@gR._+_..~..-<+z<<?<>```_.<_.(+1><_;_..(1_:`.<<??1z--(+Z!..<_.j<....`..(bgHAAQX
// @@mR.(j:..~.._<z!`.(>~``` ~(_.(+<1><><_.(((_`.<__`.<_.(X>...<_.(<.....`.JUWWWyWW
// @gmH_(zl..(.._+>```<+_````.~>``(+.<?>>_._(<```(<<``(__<>....<.._<.......dXkkkHHH
// mmqHl(dk_.(_.-=~`.`.1-..._~-1.``_:`(??<_~(`.--.&_.`.<(;<...._.._<..`..._Xg@@@@@@
// qHkpk(dX<.(;..j_```.(((JJ&a&-~``````.1<_```-(((e+.-(/`(>...._..(<......(Wmggg@@g
// HVHbWcz><__+_.(_.(dWWHHH@HHc~````````.+~`` (jHMMMHHHm&.?..._<..(<_..._.(WqqHHmHg
// 0>vWWkzZwl~<o.__`__~X@@HM@Hb ```.`.``. ```` d@@HHH@@K?76...(<..(<_...(_(ppWWWWHq
// X0XWHKXXw$<(z<.( `` WHHMHHHH_``````````````.WHHMNMHHH_`(...(<_.(z_..._<(fWVC174W
// XuXWHHWWz>__+z+.!`..??CZYCOX_`````````````.`~.OvTUZUS_`~.._+?_.(_~_.._zjO=1+~+jy
// kkkkkkkkX:._<z=1(_`` << ``->``.``.``.``.```` ?<`` (v!`._..(??_.(1._.._=dUOOzzzwX
// @@@@@@@@H<...1O=v<_...__ -_````````````````.`` `` ~.`` :.~+=?~.(;_(...jdQQQQQkkk
// H@@@@@@@H~...(==>.~~~~~....`.`````````.`````.`........->.(===~~<<.(...(dg@@@@@@@
// @@@H@@HHH_.__(=l>~.~~~~~....``.``.``.```..`......~~~~~(<_+=l=~_<.->..~_dqggggg@g
// @H@@@@MHH_._<(=l>...........```````````````.`...~~~~~~+<(=lz=~((j=z_..~jWqmmgggm
// @@H@@HHWH_._<(lll-.......```.````.``.`..`````........_z<+llZz~(lOO=<...(VYUUUW9Y
// @@HMMHWZf>~_=:=llw+.`````````.`.```__~~_``.`````.....(z+llOOz_zllOlz~..~<<1+dW>_
// MMM#MHHWXl~_=>1ltwOl&.`.``.`````.``````````````.````.(llttwtz(OltwOz<..__zwOwwOz
// HM#HMHUUI<._1z+ttOZttlt&....``.``.`.````.``...``...(zZtttOktzjttttwlz_._<(Xkkkkk
// HHHmHSZu:(_~+OztttXtttOZZttO+-..............-(+ztOttwttttd0tOZttttwOl<~.(_dMMHHH
// rvuuXuuI~~<~(uttttwvOwwwkQQHMMHHHHHHHHHMMMNmgey?OwwwrtttwXOtwttttttXtO-~.((wZyyy
// HHHHHHK>(~(-(dOrtrrl(QgMHMMMHHHHHHHHHHHHHHHH##HMNkX0rrrrXXrd%`` (Ctwwtz_~.<(Wg@H
// NNNNNHD(~(zo~zXrrrQdHHMMNMHHHHHHHHHHHHHHHHHHHHHH##HNmyrdKkwZ ` _``-zwrt1~~_<(MNM
// MMMMM#<<_jwr:(Z4QHHMMHMHHHHHHHHHHHHHHHHHHHHHHHHHHHH###NHSXZ>` ~````.OXtt>~._<?MM
*/

#include <bits/stdc++.h>
using namespace std;

using VI = vector<int>;
using VVI = vector<VI>;
using PII = pair<int, int>;
using LL = long long;
using VL = vector<LL>;
using VVL = vector<VL>;
using PLL = pair<LL, LL>;
using VS = vector<string>;

#define ALL(a)  begin((a)),end((a))
#define RALL(a) (a).rbegin(), (a).rend()
#define PB push_back
#define EB emplace_back
#define MP make_pair
#define MT make_tuple
#define SZ(a) int((a).size())
#define SORT(c) sort(ALL((c)))
#define RSORT(c) sort(RALL((c)))
#define UNIQ(c) (c).erase(unique(ALL((c))), end((c)))

#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n)  FOR(i,0,n)

#define FF first
#define SS second

template<class S, class T>
istream& operator>>(istream& is, pair<S,T>& p){
  return is >> p.FF >> p.SS;
}
template<class T>
istream& operator>>(istream& is, vector<T>& xs){
  for(auto& x: xs)
	is >> x;
  return is;
}
template<class S, class T>
ostream& operator<<(ostream& os, const pair<S,T>& p){
  return os << p.FF << " " << p.SS;
}
template<class T>
ostream& operator<<(ostream& os, const vector<T>& xs){
  for(unsigned int i=0;i<xs.size();++i)
	os << (i?" ":"") << xs[i];
  return os;
}
template<class T>
void maxi(T& x, T y){
  if(x < y) x = y;
}
template<class T>
void mini(T& x, T y){
  if(x > y) x = y;
}
void debug(istringstream&){}
template <char sep=',', class Head, class... Tail>
void debug(istringstream& iss, Head&& head, Tail&&... tail)
{
  string name;
  getline(iss, name, ',');
  cout << sep << name << "=" << head;
  debug(iss, forward<Tail>(tail)...);
}

#ifdef PYONPOI
#define DEBUG(...) \
  do{ \
    istringstream ss(#__VA_ARGS__); \
    debug<' '>(ss, __VA_ARGS__); \
    cout<<endl; \
  }while(0)
#else
#define DEBUG
#endif


const double EPS = 1e-10;
const double PI  = acos(-1.0);
const LL MOD = 1e9+7;

int main(){
  cin.tie(0);
  ios_base::sync_with_stdio(false);

  int N;
  cin >> N;
  VI xs(N+1);
  REP(i,N) cin >> xs[i+1];

  VI ans;
  for(int i=N;i>=1;--i){
    int sum = 0;
    for(int j=i+i;j<=N;j+=i){
      sum ^= xs[j];
    }

    if(xs[i] != sum){
      ans.PB(i);
    }
  }

  cout << SZ(ans) << endl;
  if(!ans.empty()) cout << ans << endl;

  return 0;
}