#include <bits/stdc++.h>
using namespace std;
long long int a[100001], b[100001];
vector<long long int> v;
map<long long int, long long int> assign;
pair<long long int, long long int> dp[1001][7001];
inline long long int gcd(long long int a, long long int b) {
  long long int tmp;
  while (b) {
    tmp = a % b;
    a = b;
    b = tmp;
  }
  return a;
}
int main() {
  ios::sync_with_stdio(false);
  ;
  cin.tie(0);
  ;
  long long int i, j, n, k, x, y, temp, sz;
  cin >> n >> k;
  temp = k;
  for (i = 1; i <= n; i++) {
    cin >> a[i];
    b[i] = gcd(a[i], k);
    temp = temp / gcd(temp, a[i]);
  }
  if (temp != 1) {
    cout << "-1";
    return 0;
  }
  if (k == 1) {
    cout << "1"
         << "\n";
    cout << min_element(a + 1, a + n + 1) - a;
    return 0;
  }
  for (i = 1; i * i <= k; i++) {
    if (k % i) continue;
    v.push_back(i);
    if (i != (k / i)) v.push_back(k / i);
  }
  sort(v.begin(), v.end());
  sz = v.size();
  for (i = 0; i < sz; i++) assign[v[i]] = i;
  for (i = 1; i < sz; i++) dp[0][i] = make_pair(1000000000000, 0);
  dp[0][0] = make_pair(0, 0);
  for (i = 1; i <= n; i++) {
    for (j = 0; j < sz; j++) {
      dp[i][j] = dp[i - 1][j];
      x = assign[v[j] / gcd(v[j], b[i])];
      if (dp[i][j] >
          make_pair(dp[i - 1][x].first + 1, dp[i - 1][x].second + a[i]))
        dp[i][j] =
            make_pair(dp[i - 1][x].first + 1, dp[i - 1][x].second + a[i]);
    }
  }
  cout << dp[n][sz - 1].first << "\n";
  x = k;
  for (i = n; i >= 1; i--) {
    if (dp[i][assign[x]] == dp[i - 1][assign[x]]) continue;
    cout << i << " ";
    x = x / gcd(x, b[i]);
  }
  return 0;
}
