#pragma region kyopro_template
#define Nyaan_template
#include <immintrin.h>
#include <bits/stdc++.h>
#define pb push_back
#define eb emplace_back
#define fi first
#define se second
#define each(x, v) for (auto &x : v)
#define all(v) (v).begin(), (v).end()
#define sz(v) ((int)(v).size())
#define mem(a, val) memset(a, val, sizeof(a))
#define ini(...)   \
  int __VA_ARGS__; \
  in(__VA_ARGS__)
#define inl(...)         \
  long long __VA_ARGS__; \
  in(__VA_ARGS__)
#define ins(...)      \
  string __VA_ARGS__; \
  in(__VA_ARGS__)
#define inc(...)    \
  char __VA_ARGS__; \
  in(__VA_ARGS__)
#define in2(s, t)                           \
  for (int i = 0; i < (int)s.size(); i++) { \
    in(s[i], t[i]);                         \
  }
#define in3(s, t, u)                        \
  for (int i = 0; i < (int)s.size(); i++) { \
    in(s[i], t[i], u[i]);                   \
  }
#define in4(s, t, u, v)                     \
  for (int i = 0; i < (int)s.size(); i++) { \
    in(s[i], t[i], u[i], v[i]);             \
  }
#define rep(i, N) for (long long i = 0; i < (long long)(N); i++)
#define repr(i, N) for (long long i = (long long)(N)-1; i >= 0; i--)
#define rep1(i, N) for (long long i = 1; i <= (long long)(N); i++)
#define repr1(i, N) for (long long i = (N); (long long)(i) > 0; i--)
#define reg(i, a, b) for (long long i = (a); i < (b); i++)
#define die(...)      \
  do {                \
    out(__VA_ARGS__); \
    return;           \
  } while (0)
using namespace std;
using ll = long long;
template <class T>
using V = vector<T>;
using vi = vector<int>;
using vl = vector<long long>;
using vvi = vector<vector<int>>;
using vd = V<double>;
using vs = V<string>;
using vvl = vector<vector<long long>>;
using P = pair<long long, long long>;
using vp = vector<P>;
using pii = pair<int, int>;
using vpi = vector<pair<int, int>>;
constexpr int inf = 1001001001;
constexpr long long infLL = (1LL << 61) - 1;
template <typename T, typename U>
inline bool amin(T &x, U y) {
  return (y < x) ? (x = y, true) : false;
}
template <typename T, typename U>
inline bool amax(T &x, U y) {
  return (x < y) ? (x = y, true) : false;
}
template <typename T, typename U>
ostream &operator<<(ostream &os, const pair<T, U> &p) {
  os << p.first << " " << p.second;
  return os;
}
template <typename T, typename U>
istream &operator>>(istream &is, pair<T, U> &p) {
  is >> p.first >> p.second;
  return is;
}
template <typename T>
ostream &operator<<(ostream &os, const vector<T> &v) {
  int s = (int)v.size();
  for (int i = 0; i < s; i++) os << (i ? " " : "") << v[i];
  return os;
}
template <typename T>
istream &operator>>(istream &is, vector<T> &v) {
  for (auto &x : v) is >> x;
  return is;
}
void in() {}
template <typename T, class... U>
void in(T &t, U &... u) {
  cin >> t;
  in(u...);
}
void out() { cout << "\n"; }
template <typename T, class... U>
void out(const T &t, const U &... u) {
  cout << t;
  if (sizeof...(u)) cout << " ";
  out(u...);
}

#ifdef NyaanDebug
#define trc(...)                   \
  do {                             \
    cerr << #__VA_ARGS__ << " = "; \
    dbg_out(__VA_ARGS__);          \
  } while (0)
#define trca(v, N)       \
  do {                   \
    cerr << #v << " = "; \
    array_out(v, N);     \
  } while (0)
#define trcc(v)                             \
  do {                                      \
    cerr << #v << " = {";                   \
    each(x, v) { cerr << " " << x << ","; } \
    cerr << "}" << endl;                    \
  } while (0)
template <typename T>
void _cout(const T &c) {
  cerr << c;
}
void _cout(const int &c) {
  if (c == 1001001001)
    cerr << "inf";
  else if (c == -1001001001)
    cerr << "-inf";
  else
    cerr << c;
}
void _cout(const unsigned int &c) {
  if (c == 1001001001)
    cerr << "inf";
  else
    cerr << c;
}
void _cout(const long long &c) {
  if (c == 1001001001 || c == (1LL << 61) - 1)
    cerr << "inf";
  else if (c == -1001001001 || c == -((1LL << 61) - 1))
    cerr << "-inf";
  else
    cerr << c;
}
void _cout(const unsigned long long &c) {
  if (c == 1001001001 || c == (1LL << 61) - 1)
    cerr << "inf";
  else
    cerr << c;
}
template <typename T, typename U>
void _cout(const pair<T, U> &p) {
  cerr << "{ ";
  _cout(p.fi);
  cerr << ", ";
  _cout(p.se);
  cerr << " } ";
}
template <typename T>
void _cout(const vector<T> &v) {
  int s = v.size();
  cerr << "{ ";
  for (int i = 0; i < s; i++) {
    cerr << (i ? ", " : "");
    _cout(v[i]);
  }
  cerr << " } ";
}
template <typename T>
void _cout(const vector<vector<T>> &v) {
  cerr << "[ ";
  for (const auto &x : v) {
    cerr << endl;
    _cout(x);
    cerr << ", ";
  }
  cerr << endl << " ] ";
}
void dbg_out() { cerr << endl; }
template <typename T, class... U>
void dbg_out(const T &t, const U &... u) {
  _cout(t);
  if (sizeof...(u)) cerr << ", ";
  dbg_out(u...);
}
template <typename T>
void array_out(const T &v, int s) {
  cerr << "{ ";
  for (int i = 0; i < s; i++) {
    cerr << (i ? ", " : "");
    _cout(v[i]);
  }
  cerr << " } " << endl;
}
template <typename T>
void array_out(const T &v, int H, int W) {
  cerr << "[ ";
  for (int i = 0; i < H; i++) {
    cerr << (i ? ", " : "");
    array_out(v[i], W);
  }
  cerr << " ] " << endl;
}
#else
#define trc(...)
#define trca(...)
#define trcc(...)
#endif

inline int popcnt(unsigned long long a) { return __builtin_popcountll(a); }
inline int lsb(unsigned long long a) { return __builtin_ctzll(a); }
inline int msb(unsigned long long a) { return 63 - __builtin_clzll(a); }
template <typename T>
inline int getbit(T a, int i) {
  return (a >> i) & 1;
}
template <typename T>
inline void setbit(T &a, int i) {
  a |= (1LL << i);
}
template <typename T>
inline void delbit(T &a, int i) {
  a &= ~(1LL << i);
}
template <typename T>
int lb(const vector<T> &v, const T &a) {
  return lower_bound(begin(v), end(v), a) - begin(v);
}
template <typename T>
int ub(const vector<T> &v, const T &a) {
  return upper_bound(begin(v), end(v), a) - begin(v);
}
template <typename T>
int btw(T a, T x, T b) {
  return a <= x && x < b;
}
template <typename T, typename U>
T ceil(T a, U b) {
  return (a + b - 1) / b;
}
constexpr long long TEN(int n) {
  long long ret = 1, x = 10;
  while (n) {
    if (n & 1) ret *= x;
    x *= x;
    n >>= 1;
  }
  return ret;
}
template <typename T>
vector<T> mkrui(const vector<T> &v) {
  vector<T> ret(v.size() + 1);
  for (int i = 0; i < int(v.size()); i++) ret[i + 1] = ret[i] + v[i];
  return ret;
};
template <typename T>
vector<T> mkuni(const vector<T> &v) {
  vector<T> ret(v);
  sort(ret.begin(), ret.end());
  ret.erase(unique(ret.begin(), ret.end()), ret.end());
  return ret;
}
template <typename F>
vector<int> mkord(int N, F f) {
  vector<int> ord(N);
  iota(begin(ord), end(ord), 0);
  sort(begin(ord), end(ord), f);
  return ord;
}
template <typename T = int>
vector<T> mkiota(int N) {
  vector<T> ret(N);
  iota(begin(ret), end(ret), 0);
  return ret;
}
template <typename T>
vector<int> mkinv(vector<T> &v) {
  vector<int> inv(v.size());
  for (int i = 0; i < (int)v.size(); i++) inv[v[i]] = i;
  return inv;
}

struct IoSetupNya {
  IoSetupNya() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    cout << fixed << setprecision(15);
    cerr << fixed << setprecision(7);
  }
} iosetupnya;

void solve();
int main() { solve(); }

#pragma endregion
using namespace std;

template <typename T, int MAX_LOG, int NODES = 16777216>
struct BinaryTrie {
  using  Container = int;
  struct Node {
    Node *nxt[2];
    int exist;
    Node() {}
  };

  Node *pool;
  int pid;
  T lazy;
  Node *nil;
  Node *root;

  BinaryTrie() : pid(0), lazy(T(0)), nil(nullptr) {
    pool = new Node[NODES];
    nil = my_new();
    nil->nxt[0] = nil->nxt[1] = root = nil;
  }

  Node *my_new(int exist_ = 0, int id = -1) {
    pool[pid].nxt[0] = pool[pid].nxt[1] = nil;
    pool[pid].exist = exist_;
    return &(pool[pid++]);
  }

  Node *merge(Node *l, Node *r) {
    pool[pid].nxt[0] = l;
    pool[pid].nxt[1] = r;
    pool[pid].exist = l->exist + r->exist;
    return &(pool[pid++]);
  }

  Node *add_(const T &x, int id, Node *n, int bit_idx = MAX_LOG) {
    if (bit_idx == -1) {
      if (n == nil) return my_new(1, id);
      n->exist++;
      return n;
    } else {
      if (((lazy >> bit_idx) & 1) == ((x >> bit_idx) & 1))
        return merge(add_(x, id, n->nxt[0], bit_idx - 1), n->nxt[1]);
      else
        return merge(n->nxt[0], add_(x, id, n->nxt[1], bit_idx - 1));
    }
  }

 public:
  void add(const T &x, int id = -1) { root = add_(x, id, root, MAX_LOG); }

  Node *del_(const T &x, int id, Node *n, int bit_idx = MAX_LOG) {
    if (bit_idx == -1) {
      n->exist--;
      return n;
    } else {
      if (((lazy >> bit_idx) & 1) == ((x >> bit_idx) & 1))
        return merge(del_(x, id, n->nxt[0], bit_idx - 1), n->nxt[1]);
      else
        return merge(n->nxt[0], del_(x, id, n->nxt[1], bit_idx - 1));
    }
  }

 public:
  void del(const T &x, int id = -1) { root = del_(x, id, root, MAX_LOG); }

  pair<int, const Container &> find_(const T &x, Node *n, int bit_idx = MAX_LOG) {
    if (bit_idx == -1)
      return pair<int, const Container &>(n->exist, 0);
    else {
      if (((lazy >> bit_idx) & 1) == ((x >> bit_idx) & 1))
        return find_(x, n->nxt[0], bit_idx - 1);
      else
        return find_(x, n->nxt[1], bit_idx - 1);
    }
  }

 public:
  pair<int, const Container &> find(const T &x) { return find_(x, root, MAX_LOG); }

 private:
  pair<T, const Container &> max_element_(Node *n, int bit_idx = MAX_LOG) {
    if (bit_idx == -1) return pair<T, const Container &>(0,0);
    if (n->nxt[~(lazy >> bit_idx) & 1]->exist) {
      auto ret = max_element_(n->nxt[~(lazy >> bit_idx) & 1], bit_idx - 1);
      ret.first |= T(1) << bit_idx;
      return ret;
    } else {
      return max_element_(n->nxt[(lazy >> bit_idx) & 1], bit_idx - 1);
    }
  }

 public:
  pair<T, const Container &> max_element() { return max_element_(root, MAX_LOG); }

 private:
  pair<T, const Container &> min_element_(Node *n, int bit_idx = MAX_LOG) {
    if (bit_idx == -1) return pair<T, const Container &>(0, 0);
    if (n->nxt[(lazy >> bit_idx) & 1]->exist) {
      return min_element_(n->nxt[(lazy >> bit_idx) & 1], bit_idx - 1);
    } else {
      auto ret = min_element_(n->nxt[~(lazy >> bit_idx) & 1], bit_idx - 1);
      ret.first |= T(1) << bit_idx;
      return ret;
    }
  }

 public:
  pair<T, const Container &> min_element() { return min_element_(root, MAX_LOG); }

 private:
  pair<T, const Container &> get_kth_(Node *n, int64_t k, int bit_idx = MAX_LOG) {
    if (bit_idx == -1) return pair<T, const Container &>(0, 0);
    int ex0 = n->nxt[(lazy >> bit_idx) & 1]->exist;
    if (ex0 < k) {
      auto ret = get_kth_(n->nxt[~(lazy >> bit_idx) & 1], k - ex0, bit_idx - 1);
      ret.first |= T(1) << bit_idx;
      return ret;
    } else {
      return get_kth_(n->nxt[(lazy >> bit_idx) & 1], k, bit_idx - 1);
    }
  }

 public:
  T mex_query_(Node *n, int bit_index = MAX_LOG) {  // distinct-values
    assert(lazy == 0);
    if (bit_index == -1 || n->nxt[0] == nil) return 0;
    if (n->nxt[0]->exist == (T(1) << bit_index)) {
      T ret = T(1) << bit_index;
      if (n->nxt[1]) ret |= mex_query_(n->nxt[1], bit_index - 1);
      return ret;
    } else {
      return mex_query_(n->nxt[0], bit_index - 1);
    }
  }

 public:
  pair<T, const Container &> get_kth(int64_t k) { return get_kth_(root, k, MAX_LOG); }

  void operate_xor(T x) { lazy ^= x; }
};

/**
 * @brief Binary Trie
 * @docs docs/binary-trie.md
 */

using namespace std;

template <typename T>
struct edge {
  int src, to;
  T cost;

  edge(int to, T cost) : src(-1), to(to), cost(cost) {}
  edge(int src, int to, T cost) : src(src), to(to), cost(cost) {}

  edge &operator=(const int &x) {
    to = x;
    return *this;
  }

  operator int() const { return to; }
};
template <typename T>
using Edges = vector<edge<T>>;
template <typename T>
using WeightedGraph = vector<Edges<T>>;
using UnweightedGraph = vector<vector<int>>;

// Input of (Unweighted) Graph
UnweightedGraph graph(int N, int M = -1, bool is_directed = false,
                      bool is_1origin = true) {
  UnweightedGraph g(N);
  if (M == -1) M = N - 1;
  for (int _ = 0; _ < M; _++) {
    int x, y;
    cin >> x >> y;
    if (is_1origin) x--, y--;
    g[x].push_back(y);
    if (!is_directed) g[y].push_back(x);
  }
  return g;
}

// Input of Weighted Graph
template <typename T>
WeightedGraph<T> wgraph(int N, int M = -1, bool is_directed = false,
                        bool is_1origin = true) {
  WeightedGraph<T> g(N);
  if (M == -1) M = N - 1;
  for (int _ = 0; _ < M; _++) {
    int x, y;
    cin >> x >> y;
    T c;
    cin >> c;
    if (is_1origin) x--, y--;
    g[x].eb(x, y, c);
    if (!is_directed) g[y].eb(y, x, c);
  }
  return g;
}

// Input of Edges
template <typename T>
Edges<T> esgraph(int N, int M, int is_weighted = true, bool is_1origin = true) {
  Edges<T> es;
  for (int _ = 0; _ < M; _++) {
    int x, y;
    cin >> x >> y;
    T c;
    if (is_weighted)
      cin >> c;
    else
      c = 1;
    if (is_1origin) x--, y--;
    es.emplace_back(x, y, c);
  }
  return es;
}

// Input of Adjacency Matrix
template <typename T>
vector<vector<T>> adjgraph(int N, int M, T INF, int is_weighted = true,
                           bool is_directed = false, bool is_1origin = true) {
  vector<vector<T>> d(N, vector<T>(N, INF));
  for (int _ = 0; _ < M; _++) {
    int x, y;
    cin >> x >> y;
    T c;
    if (is_weighted)
      cin >> c;
    else
      c = 1;
    if (is_1origin) x--, y--;
    d[x][y] = c;
    if (!is_directed) d[y][x] = c;
  }
  return d;
}
using namespace std;


// Depth of Rooted Tree
// unvisited nodes : d = -1
vector<int> Depth(const UnweightedGraph &g, int start = 0) {
  vector<int> d(g.size(), -1);
  auto dfs = [&](auto rec, int cur, int par = -1) -> void {
    d[cur] = par == -1 ? 0 : d[par] + 1;
    for (auto &dst : g[cur]) {
      if (dst == par) continue;
      rec(rec, dst, cur);
    }
  };
  dfs(dfs, start);
  return d;
}

// Depth of Rooted Weighted Tree
// unvisited nodes : d = -1
template <typename T>
vector<T> Depth(const WeightedGraph<T> &g, int start = 0) {
  vector<T> d(g.size(), -1);
  auto dfs = [&](auto rec, int cur, T val, int par = -1) -> void {
    d[cur] = val;
    for (auto &dst : g[cur]) {
      if (dst == par) continue;
      rec(rec, dst, val + dst.cost, cur);
    }
  };
  dfs(dfs, start, 0);
  return d;
}

// Diameter of Tree
// return value : { {u, v}, length }
pair<pair<int, int>, int> Diameter(const UnweightedGraph &g) {
  auto d = Depth(g, 0);
  int u = max_element(begin(d), end(d)) - begin(d);
  d = Depth(g, u);
  int v = max_element(begin(d), end(d)) - begin(d);
  return make_pair(make_pair(u, v), d[v]);
}

// Diameter of Weighted Tree
// return value : { {u, v}, length }
template <typename T>
pair<pair<int, int>, T> Diameter(const WeightedGraph<T> &g) {
  auto d = Depth(g, 0);
  int u = max_element(begin(d), end(d)) - begin(d);
  d = Depth(g, u);
  int v = max_element(begin(d), end(d)) - begin(d);
  return make_pair(make_pair(u, v), d[v]);
}

// nodes on the path u-v ( O(N) )
template <typename G>
vector<int> Path(G &g, int u, int v) {
  vi ret;
  int end = 0;
  auto dfs = [&](auto rec, int cur, int par = -1) -> void {
    ret.push_back(cur);
    if (cur == v) {
      end = 1;
      return;
    }
    for (int dst : g[cur]) {
      if (dst == par) continue;
      rec(rec, dst, cur);
      if (end) return;
    }
    if (end) return;
    ret.pop_back();
  };
  dfs(dfs, u);
  return ret;
}
using namespace std;


template <typename G>
struct HeavyLightDecomposition {
  G& g;
  int idx;
  vector<int> size, depth, in, out, nxt, par;
  HeavyLightDecomposition(G& g, int root = 0)
      : g(g),
        idx(0),
        size(g.size(), 0),
        depth(g.size(), 0),
        in(g.size(), -1),
        out(g.size(), -1),
        nxt(g.size(), root),
        par(g.size(), root) {
    dfs_sz(root);
    dfs_hld(root);
  }

  void build(int root) {
    dfs_sz(root);
    dfs_hld(root);
  }

  void dfs_sz(int cur) {
    size[cur] = 1;
    for (auto& dst : g[cur]) {
      if (dst == par[cur]) {
        if (g[cur].size() >= 2 && int(dst) == int(g[cur][0]))
          swap(g[cur][0], g[cur][1]);
        else
          continue;
      }
      depth[dst] = depth[cur] + 1;
      par[dst] = cur;
      dfs_sz(dst);
      size[cur] += size[dst];
      if (size[dst] > size[g[cur][0]]) {
        swap(dst, g[cur][0]);
      }
    }
  }

  void dfs_hld(int cur) {
    in[cur] = idx++;
    for (auto dst : g[cur]) {
      if (dst == par[cur]) continue;
      nxt[dst] = (int(dst) == int(g[cur][0]) ? nxt[cur] : int(dst));
      dfs_hld(dst);
    }
    out[cur] = idx;
  }

  template <typename F>
  void edge_query(int u, int v, const F& f) {
    while (1) {
      if (in[u] > in[v]) swap(u, v);
      if (nxt[u] != nxt[v]) {
        f(in[nxt[v]], in[v] + 1);
        v = par[nxt[v]];
      } else {
        if (u != v) f(in[u] + 1, in[v] + 1);
        break;
      }
    }
  }

  // TODO : verify
  template <typename F>
  void uncommutable_edge_query(int u, int v, const F& f) {
    while (1) {
      if (nxt[u] != nxt[v]) {
        if (in[u] > in[v]) {
          f(in[u] + 1, in[nxt[u]], true);
          u = par[nxt[u]];
        } else {
          f(in[nxt[v]], in[v] + 1, false);
          v = par[nxt[v]];
        }
      } else {
        if (in[u] != in[v]) {
          if (in[u] > in[v])
            f(in[u] + 1, in[v] + 1, true);
          else
            f(in[u] + 1, in[v] + 1, true);
        }
        break;
      }
    }
  }

  template <typename F>
  void node_query(int u, int v, const F& f) {
    while (1) {
      if (in[u] > in[v]) swap(u, v);
      if (nxt[u] != nxt[v]) {
        f(in[nxt[v]], in[v] + 1);
        v = par[nxt[v]];
      } else {
        f(in[u], in[v] + 1);
        break;
      }
    }
  }

  template <typename F>
  void uncommutable_node_query(int u, int v, const F& f) {
    while (1) {
      if (nxt[u] != nxt[v]) {
        if (in[u] > in[v]) {
          f(in[u] + 1, in[nxt[u]], true);
          u = par[nxt[u]];
        } else {
          f(in[nxt[v]], in[v] + 1, false);
          v = par[nxt[v]];
        }
      } else {
        if (in[u] > in[v])
          f(in[u] + 1, in[v], true);
        else
          f(in[u], in[v] + 1, true);
        break;
      }
    }
  }

  template <typename F>
  void sub_edge_query(int u, const F& f) {
    f(in[u] + 1, out[u]);
  }

  template <typename F>
  void sub_node_query(int u, const F& f) {
    f(in[u], out[u]);
  }

  int lca(int a, int b) {
    while (nxt[a] != nxt[b]) {
      if (in[a] < in[b]) swap(a, b);
      a = par[nxt[a]];
    }
    return depth[a] < depth[b] ? a : b;
  }
};

void solve() {
  ini(N, M);
  vl a(M);
  in(a);
  each(x, a) x--;

  auto g = graph(N);
  auto dep = Depth(g);
  // HeavyLightDecomposition<vvi> hld(g);
  BinaryTrie<int, 18, 16777216> trie;

  vi sub(N);
  {
    auto dfs = [&](auto rec, int cur, int par = -1) -> int {
      auto root = trie.nil;
      each(dst, g[cur]) {
        if (dst == par) continue;
        int val = rec(rec, dst, cur);
        if (trie.find_(val, root).first == 0) root = trie.add_(val, -1, root);
      }
      sub[cur] = trie.mex_query_(root);
      return sub[cur];
    };
    dfs(dfs, 0);
  }
  trc(sub);

  // HeavyLightDecomposition<vvi> hld(g);
  trie.pid = 1;
  vi ans(N);
  {
    auto dfs = [&](auto rec, int cur, int pval, int par = -1) -> void {
      auto root = trie.nil;
      unordered_map<int, int> m;
      root = trie.add_(pval, -1, root);
      m[pval]++;
      each(dst, g[cur]) {
        if (dst == par) continue;
        if (m[sub[dst]] == 0) root = trie.add_(sub[dst], -1, root);
        m[sub[dst]]++;
      }

      ans[cur] = trie.mex_query_(root, 18);
      each(dst, g[cur]) {
        if (dst == par) continue;
        if (m[sub[dst]] == 1) root = trie.del_(sub[dst], -1, root);
        rec(rec, dst, trie.mex_query_(root), cur);
        if (m[sub[dst]] == 1) root = trie.add_(sub[dst], -1, root);
      }
    };
    dfs(dfs, 0, (1 << 18) - 1);
  }
  trc(ans);

  int xor_ = 0;
  each(x, a) xor_ ^= ans[x];
  if (xor_ == 0) {
    die(-1, -1);
  }
  set<int> cnt;
  each(x, a) cnt.insert(x);
  each(cur, cnt) {
    int p = -1;
    each(dst, g[cur]) {
      if (dep[dst] < dep[cur]) {
        p = dst;
        continue;
      }
      if ((ans[cur] ^ sub[dst] ^ xor_) == 0) {
        // これが答え
        int i = -1;
        rep(_, M) if (a[_] == cur) i = _;
        out(i + 1, dst + 1);
        return;
      }
    }
    if (p != -1 and (ans[cur] ^ xor_) < ans[cur]){
      int i = -1;
      rep(_, M) if (a[_] == cur) i = _;
      die(i + 1, p + 1);
    }
  }
  exit(1);
}