#include <bits/stdc++.h>
using namespace std;
const int N = (int)2e5 + 123;
const int MOD = (int)1e9 + 7;
const int inf = (int)5e8;
const long long infll = (long long)1e17;
int a[N];
vector<int> on_step[N];
int p1[N];
int p2[N];
void solve() {
  int h;
  scanf("%d", &h);
  for (int i = 0; i < h + 1; ++i) {
    scanf("%d", &a[i]);
  }
  p1[0] = p2[0] = -1;
  on_step[0].push_back(0);
  int n = 1;
  bool ok = false;
  for (int i = 1; i <= h; ++i) {
    if (a[i] > 1 && a[i - 1] > 1 && !ok) {
      for (int j = 0; j < a[i]; ++j) {
        p1[n] = p2[n] = on_step[i - 1][0];
        if (j + 1 == a[i]) {
          p2[n] = on_step[i - 1][1];
        }
        on_step[i].push_back(n++);
      }
      ok = true;
    } else {
      for (int j = 0; j < a[i]; ++j) {
        p1[n] = p2[n] = on_step[i - 1][0];
        on_step[i].push_back(n++);
      }
    }
  }
  if (!ok) {
    printf("perfect\n");
  } else {
    printf("ambiguous\n");
    for (int i = 0; i < n; ++i) {
      printf("%d ", p1[i] + 1);
    }
    printf("\n");
    for (int i = 0; i < n; ++i) {
      printf("%d ", p2[i] + 1);
    }
    printf("\n");
  }
}
int main() {
  int t = 1;
  while (t--) {
    solve();
  }
  return 0;
}
