#include <bits/stdc++.h>
using namespace std;
const int maxn = 1e5 + 10;
struct node {
  int x;
  int id;
} a[maxn], b[maxn];
int n;
bool cmp(const node& aa, const node& bb) { return aa.x > bb.x; }
int main() {
  scanf("%d", &n);
  for (int i = 0; i < n; i++) {
    scanf("%d", &a[i].x);
    a[i].id = i + 1;
  }
  for (int i = 0; i < n; i++) {
    scanf("%d", &b[i].x);
    b[i].id = i + 1;
  }
  printf("%d\n", n / 2 + 1);
  sort(a, a + n, cmp);
  printf("%d", a[0].id);
  for (int i = 1; i < n; i += 2) {
    if (b[a[i].id - 1].x > b[a[i + 1].id - 1].x) {
      printf(" %d", a[i].id);
    } else {
      printf(" %d", a[i + 1].id);
    }
  }
  { printf("\n"); }
  return 0;
}
