#include <bits/stdc++.h>   using namespace std;   const long long mod = 1e9 + 7, mod2 = 998244353;   unsigned long long base = 131;   const int w = 5e5 + 5;   long long n, m;   struct node {     int x, y, z;   } s[w];   int cmp(node x, node y) {     if (x.x != y.x)       return x.x > y.x;     else       return x.y > y.y;   }   int main() {     long long i, j, t;     cin >> n;     cout << n / 2 + 1 << endl;     for (i = 1; i <= n; i++) scanf( %d , &s[i].x), s[i].z = i;     for (i = 1; i <= n; i++) scanf( %d , &s[i].y);     sort(s + 1, s + 1 + n, cmp);     cout << s[1].z <<    ;     for (i = 2; i <= n; i += 2) {       if (s[i].y > s[i + 1].y)         cout << s[i].z <<    ;       else         cout << s[i + 1].z <<    ;     }     return 0;   }   