#include <bits/stdc++.h>
using namespace std;
int n, m;
long long a[200005], b[200005];
vector<char> ans;
inline long long read() {
  long long x = 0, f = 1;
  char ch = getchar();
  for (; ch < '0' || ch > '9'; ch = getchar())
    if (ch == '-') f = -1;
  for (; ch >= '0' && ch <= '9'; ch = getchar()) x = x * 10 + ch - '0';
  return x * f;
}
int main() {
  n = read();
  for (int i = 1; i <= n; i++) a[i] = read();
  for (int i = 1; i <= n; i++) b[i] = read();
  if (n == 1) {
    if (a[1] == b[1])
      puts("small\n0\n");
    else
      puts("impossible");
    return 0;
  }
  if (n == 2) {
    bool can = 0;
    long long ans = 0;
    long long x = b[1], y = b[2], tx = a[1], ty = a[2];
    if (tx > ty) swap(tx, ty);
    if (x > y) swap(x, y);
    while (1) {
      if (x == tx && abs(y - ty) % x == 0) {
        ans += (y - ty) / x;
        can = 1;
        break;
      }
      if (x == 0) break;
      ans += y / x;
      long long t = y;
      y = x, x = t % x;
    }
    if (!can) {
      puts("impossible");
      return 0;
    }
    if (ans > 2e5) {
      printf("big\n%lld\n", ans);
      return 0;
    }
  }
  int cnt = 0;
  bool can = 0;
  while (1) {
    bool flag = 1;
    for (int i = 1; i <= n; i++)
      if (a[i] != b[i]) {
        flag = 0;
        break;
      }
    if (flag) {
      can = 1;
      break;
    }
    flag = 1;
    for (int i = 1; i <= n; i++)
      if (a[i] != b[n - i + 1]) {
        flag = 0;
        break;
      }
    if (flag) {
      can = 1;
      ans.push_back('R');
      break;
    }
    if (b[1] > b[2]) reverse(b + 1, b + n + 1), ans.push_back('R');
    flag = 1;
    for (int i = 1; i < n; i++)
      if (b[i] >= b[i + 1]) {
        flag = 0;
        break;
      }
    if (!flag) break;
    for (int i = n; i; i--) b[i] -= b[i - 1];
    ans.push_back('P');
    ++cnt;
  }
  if (!can)
    puts("impossible");
  else if (cnt > 2e5)
    printf("big\n%d\n", cnt);
  else {
    puts("small");
    printf("%d\n", (int)ans.size());
    reverse(ans.begin(), ans.end());
    for (char c : ans) putchar(c);
    puts("");
  }
  return 0;
}
