/**
 *  date : 2021-12-06 23:02:06
 */

#define NDEBUG
using namespace std;

// intrinstic
#include <immintrin.h>

#include <algorithm>
#include <array>
#include <bitset>
#include <cassert>
#include <cctype>
#include <cfenv>
#include <cfloat>
#include <chrono>
#include <cinttypes>
#include <climits>
#include <cmath>
#include <complex>
#include <cstdarg>
#include <cstddef>
#include <cstdint>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <deque>
#include <fstream>
#include <functional>
#include <initializer_list>
#include <iomanip>
#include <ios>
#include <iostream>
#include <istream>
#include <iterator>
#include <limits>
#include <list>
#include <map>
#include <memory>
#include <new>
#include <numeric>
#include <ostream>
#include <queue>
#include <random>
#include <set>
#include <sstream>
#include <stack>
#include <streambuf>
#include <string>
#include <tuple>
#include <type_traits>
#include <typeinfo>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>

// utility
namespace Nyaan {
using ll = long long;
using i64 = long long;
using u64 = unsigned long long;
using i128 = __int128_t;
using u128 = __uint128_t;

template <typename T>
using V = vector<T>;
template <typename T>
using VV = vector<vector<T>>;
using vi = vector<int>;
using vl = vector<long long>;
using vd = V<double>;
using vs = V<string>;
using vvi = vector<vector<int>>;
using vvl = vector<vector<long long>>;

template <typename T, typename U>
struct P : pair<T, U> {
  template <typename... Args>
  P(Args... args) : pair<T, U>(args...) {}

  using pair<T, U>::first;
  using pair<T, U>::second;

  T &x() { return first; }
  const T &x() const { return first; }
  U &y() { return second; }
  const U &y() const { return second; }

  P &operator+=(const P &r) {
    first += r.first;
    second += r.second;
    return *this;
  }
  P &operator-=(const P &r) {
    first -= r.first;
    second -= r.second;
    return *this;
  }
  P &operator*=(const P &r) {
    first *= r.first;
    second *= r.second;
    return *this;
  }
  P operator+(const P &r) const { return P(*this) += r; }
  P operator-(const P &r) const { return P(*this) -= r; }

  P operator*(const P &r) const { return P(*this) *= r; }

  P operator*(int r) const { return {first * r, second * r}; }

  P operator-() const { return P{-first, -second}; }
};

using pl = P<ll, ll>;
using pi = P<int, int>;
using vp = V<pl>;

constexpr int inf = 1001001001;
constexpr long long infLL = 4004004004004004004LL;

template <typename T>
int sz(const T &t) {
  return t.size();
}

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>
inline T Max(const vector<T> &v) {
  return *max_element(begin(v), end(v));
}
template <typename T>
inline T Min(const vector<T> &v) {
  return *min_element(begin(v), end(v));
}
template <typename T>
inline long long Sum(const vector<T> &v) {
  return accumulate(begin(v), end(v), 0LL);
}

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);
}

constexpr long long TEN(int n) {
  long long ret = 1, x = 10;
  for (; n; x *= x, n >>= 1) ret *= (n & 1 ? x : 1);
  return ret;
}

template <typename T, typename U>
pair<T, U> mkp(const T &t, const U &u) {
  return make_pair(t, u);
}

template <typename T>
vector<T> mkrui(const vector<T> &v, bool rev = false) {
  vector<T> ret(v.size() + 1);
  if (rev) {
    for (int i = int(v.size()) - 1; i >= 0; i--) ret[i] = v[i] + ret[i + 1];
  } else {
    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>
vector<int> mkinv(vector<T> &v) {
  int max_val = *max_element(begin(v), end(v));
  vector<int> inv(max_val + 1, -1);
  for (int i = 0; i < (int)v.size(); i++) inv[v[i]] = i;
  return inv;
}

}  // namespace Nyaan

// bit operation
namespace Nyaan {
__attribute__((target("popcnt"))) inline int popcnt(const u64 &a) {
  return _mm_popcnt_u64(a);
}
inline int lsb(const u64 &a) { return a ? __builtin_ctzll(a) : 64; }
inline int ctz(const u64 &a) { return a ? __builtin_ctzll(a) : 64; }
inline int msb(const u64 &a) { return a ? 63 - __builtin_clzll(a) : -1; }
template <typename T>
inline int gbit(const T &a, int i) {
  return (a >> i) & 1;
}
template <typename T>
inline void sbit(T &a, int i, bool b) {
  if (gbit(a, i) != b) a ^= T(1) << i;
}
constexpr long long PW(int n) { return 1LL << n; }
constexpr long long MSK(int n) { return (1LL << n) - 1; }
}  // namespace Nyaan

// inout
namespace Nyaan {

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, char sep = ' '>
void out(const T &t, const U &... u) {
  cout << t;
  if (sizeof...(u)) cout << sep;
  out(u...);
}

void outr() {}
template <typename T, class... U, char sep = ' '>
void outr(const T &t, const U &... u) {
  cout << t;
  outr(u...);
}

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

}  // namespace Nyaan

// debug
namespace DebugImpl {

template <typename U, typename = void>
struct is_specialize : false_type {};
template <typename U>
struct is_specialize<
    U, typename conditional<false, typename U::iterator, void>::type>
    : true_type {};
template <typename U>
struct is_specialize<
    U, typename conditional<false, decltype(U::first), void>::type>
    : true_type {};
template <typename U>
struct is_specialize<U, enable_if_t<is_integral<U>::value, void>> : true_type {
};

void dump(const char& t) { cerr << t; }

void dump(const string& t) { cerr << t; }

void dump(const bool& t) { cerr << (t ? "true" : "false"); }

template <typename U,
          enable_if_t<!is_specialize<U>::value, nullptr_t> = nullptr>
void dump(const U& t) {
  cerr << t;
}

template <typename T>
void dump(const T& t, enable_if_t<is_integral<T>::value>* = nullptr) {
  string res;
  if (t == Nyaan::inf) res = "inf";
  if constexpr (is_signed<T>::value) {
    if (t == -Nyaan::inf) res = "-inf";
  }
  if constexpr (sizeof(T) == 8) {
    if (t == Nyaan::infLL) res = "inf";
    if constexpr (is_signed<T>::value) {
      if (t == -Nyaan::infLL) res = "-inf";
    }
  }
  if (res.empty()) res = to_string(t);
  cerr << res;
}

template <typename T, typename U>
void dump(const pair<T, U>&);
template <typename T>
void dump(const pair<T*, int>&);

template <typename T>
void dump(const T& t,
          enable_if_t<!is_void<typename T::iterator>::value>* = nullptr) {
  cerr << "[ ";
  for (auto it = t.begin(); it != t.end();) {
    dump(*it);
    cerr << (++it == t.end() ? "" : ", ");
  }
  cerr << " ]";
}

template <typename T, typename U>
void dump(const pair<T, U>& t) {
  cerr << "( ";
  dump(t.first);
  cerr << ", ";
  dump(t.second);
  cerr << " )";
}

template <typename T>
void dump(const pair<T*, int>& t) {
  cerr << "[ ";
  for (int i = 0; i < t.second; i++) {
    dump(t.first[i]);
    cerr << (i == t.second - 1 ? "" : ", ");
  }
  cerr << " ]";
}

void trace() { cerr << endl; }
template <typename Head, typename... Tail>
void trace(Head&& head, Tail&&... tail) {
  cerr << " ";
  dump(head);
  if (sizeof...(tail) != 0) cerr << ",";
  trace(forward<Tail>(tail)...);
}

}  // namespace DebugImpl

#ifdef NyaanDebug
#define trc(...)                            \
  do {                                      \
    cerr << "## " << #__VA_ARGS__ << " = "; \
    DebugImpl::trace(__VA_ARGS__);          \
  } while (0)
#else
#define trc(...) (void(0))
#endif

// macro
#define each(x, v) for (auto&& x : v)
#define each2(x, y, v) for (auto&& [x, y] : v)
#define all(v) (v).begin(), (v).end()
#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 regr(i, a, b) for (long long i = (b)-1; i >= (a); i--)
#define fi first
#define se second
#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 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 die(...)             \
  do {                       \
    Nyaan::out(__VA_ARGS__); \
    return;                  \
  } while (0)

namespace Nyaan {
void solve();
}
int main() { Nyaan::solve(); }

//

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].emplace_back(x, y, c);
    if (!is_directed) g[y].emplace_back(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;
}

namespace my_rand {

// [0, 2^64 - 1)
uint64_t rng() {
  static uint64_t x_ =
      uint64_t(chrono::duration_cast<chrono::nanoseconds>(
                   chrono::high_resolution_clock::now().time_since_epoch())
                   .count()) *
      10150724397891781847ULL;
  x_ ^= x_ << 7;
  return x_ ^= x_ >> 9;
}

// [l, r)
int64_t randint(int64_t l, int64_t r) {
  assert(l < r);
  return l + rng() % (r - l);
}

// choose n numbers from [l, r) without overlapping
vector<int64_t> randset(int64_t l, int64_t r, int64_t n) {
  assert(l <= r && n <= r - l);
  unordered_set<int64_t> s;
  for (int64_t i = n; i; --i) {
    int64_t m = randint(l, r + 1 - i);
    if (s.find(m) != s.end()) m = r - i;
    s.insert(m);
  }
  vector<int64_t> ret;
  for (auto& x : s) ret.push_back(x);
  return ret;
}

// [0.0, 1.0)
double rnd() {
  union raw_cast {
    double t;
    uint64_t u;
  };
  constexpr uint64_t p = uint64_t(1023 - 64) << 52;
  return rng() * ((raw_cast*)(&p))->t;
}

template <typename T>
void randshf(vector<T>& v) {
  int n = v.size();
  for (int loop = 0; loop < 2; loop++)
    for (int i = 0; i < n; i++) swap(v[i], v[randint(0, n)]);
}

}  // namespace my_rand

using my_rand::randint;
using my_rand::randset;
using my_rand::randshf;
using my_rand::rnd;
using my_rand::rng;



struct Timer {
  chrono::high_resolution_clock::time_point st;

  Timer() { reset(); }

  void reset() { st = chrono::high_resolution_clock::now(); }

  chrono::milliseconds::rep elapsed() {
    auto ed = chrono::high_resolution_clock::now();
    return chrono::duration_cast<chrono::milliseconds>(ed - st).count();
  }
};

using namespace Nyaan;
using ull = uint64_t;

// http://yosupo06.github.io/Algorithm/src/nimber.test.cpp
struct Nimber64;
Nimber64 mul_naive(Nimber64 l, Nimber64 r);
struct Nimber64 {
  const static V<ull> factor;
  const static array<array<unsigned char, 256>, 256> small;
  const static array<array<array<Nimber64, 256>, 8>, 8> precalc;
  ull v;
  Nimber64() : v(0) {}
  Nimber64(ull _v) : v(_v) {}
  const Nimber64 operator+(Nimber64 r) const { return v ^ r.v; }
  const Nimber64 operator*(Nimber64 r) const {
    Nimber64 ans;
    for (int i = 0; i < 8; i++) {
      for (int j = 0; j < 8; j++) {
        ull x = (v >> (8 * i)) % 256;
        ull y = (r.v >> (8 * j)) % 256;
        ans += precalc[i][j][small[x][y]];
      }
    }
    return ans;
  }
  bool operator==(Nimber64 r) const { return v == r.v; }
  Nimber64& operator+=(Nimber64 r) { return *this = *this + r; }
  Nimber64& operator*=(Nimber64 r) { return *this = *this * r; }

  Nimber64 pow(ull n) const {
    Nimber64 x = *this, r = 1;
    while (n) {
      if (n & 1) r = r * x;
      x = x * x;
      n >>= 1;
    }
    return r;
  }

  ull discrete_logarithm(Nimber64 y) {
    ull rem = 0, mod = 1;
    for (ull p : factor) {
      ull STEP = 1;
      while (4 * STEP * STEP < p) STEP *= 2;
      auto inside = [&](Nimber64 x, Nimber64 z) {
        unordered_map<ull, int> mp;
        Nimber64 big = 1;  // x^m
        for (int i = 0; i < int(STEP); i++) {
          mp[z.v] = i;
          z *= x;
          big *= x;
        }
        Nimber64 now = 1;
        for (int step = 0; step < int(p + 10); step += STEP) {
          now *= big;
          // check [step + 1, step + STEP]
          if (mp.find(now.v) != mp.end()) {
            return (step + STEP) - mp[now.v];
          }
        }
        return ull(-1);
      };

      ull q = ull(-1) / p;
      ull res = inside((*this).pow(q), y.pow(q));
      if (res == ull(-1)) {
        return ull(-1);
      }
      res %= p;
      // mod p = v
      if (mod == 1) {
        rem = res;
        mod = p;
      } else {
        while (rem % p != res) rem += mod;
        mod *= p;
      }
    }
    return rem;
  }

  bool is_primitive_root() const {
    for (ull p : factor) {
      if ((*this).pow(ull(-1) / p).v == 1) return false;
    }
    return true;
  }
};
const V<ull> Nimber64::factor = {
    6700417, 65537, 641, 257, 17, 5, 3,
};

Nimber64 mul_naive(Nimber64 l, Nimber64 r) {
  ull a = l.v, b = r.v;
  if (a < b) swap(a, b);
  if (b == 0) return 0;
  if (b == 1) return a;
  int p = 32;
  while (max(a, b) < (1ULL << p)) p /= 2;
  ull power = 1ULL << p;
  if (a >= power && b >= power) {
    Nimber64 ans;
    ans += mul_naive(a % power, b % power);
    ans += mul_naive(a / power, b % power).v * power;
    ans += mul_naive(a % power, b / power).v * power;
    auto x = mul_naive(a / power, b / power);
    ans += x.v * power;
    ans += mul_naive(x.v, power / 2);
    return ans;
  } else {
    return Nimber64(mul_naive(a / power, b).v * power) +
           mul_naive(a % power, b);
  }
};

const array<array<unsigned char, 256>, 256> Nimber64::small = []() {
  array<array<unsigned char, 256>, 256> _small;
  for (int i = 0; i < 256; i++) {
    for (int j = 0; j < 256; j++) {
      _small[i][j] = (unsigned char)(mul_naive(i, j).v);
    }
  }
  return _small;
}();

const array<array<array<Nimber64, 256>, 8>, 8> Nimber64::precalc = []() {
  array<array<array<Nimber64, 256>, 8>, 8> _precalc;
  for (int i = 0; i < 8; i++) {
    for (int j = 0; j < 8; j++) {
      for (int k = 0; k < 256; k++) {
        _precalc[i][j][k] =
            mul_naive(mul_naive(1ULL << (8 * i), 1ULL << (8 * j)), k);
      }
    }
  }
  return _precalc;
}();

u64 nim_product(u64 a, u64 b) { return (Nimber64(a) * Nimber64(b)).v; }

// y 訪問済み / z 訪問済み / 今のマス / 前のマス
u64 dp[2][2][128][128];
u64 nx[2][2][128][128];

void Nyaan::solve() {
  Timer timer;
  inl(N, M, X, Y, Z);
  --X, --Y, --Z;
  vvl g(N, vl(N));
  rep(i, M) {
    inl(u, v);
    --u, --v;
    g[u][v] = g[v][u] = 1;
  }
  Edges<u64> es;
  rep(i, N) rep(j, i) {
    if (g[i][j] == 1) continue;
    u64 x = rng() % u64(-1) + 1;
    es.emplace_back(i, j, x);
    /*
    if (i == X or j == X) {
      x = rng() % u64(-1) + 1;
    }
    */
    es.emplace_back(j, i, x);
  }
  sort(all(es), [](edge<u64>& u, edge<u64>& v) {
    if (u.src != v.src) return u.src < v.src;
    return u.to < v.to;
  });

  // y 訪問済み / z 訪問済み / 今のマス / 前のマス
  dp[0][0][X][X] = 1;
  rep1(L, N) {
    //if (timer.elapsed() > 7000) exit(1);
    memset(nx, 0, sizeof(nx));
    rep(ky, 2) rep(kz, 2) {
      each(e, es) {
        int c = e.src;
        int d = e.to;
        u64 w = e.cost;
        if(ky == 1 and d == Y) continue;
        if(kz == 1 and d == Z) continue;
        int nky = ky | (d == Y);
        int nkz = kz | (d == Z);
        rep(p, N) {
          if (p == d) continue;
          if (dp[ky][kz][c][p] == 0) continue;
          nx[nky][nkz][d][c] ^= nim_product(dp[ky][kz][c][p], w);
        }
      }
    }
    swap(dp, nx);

    /*
    reg(ky, 1, 2) reg(kz, 1, 2) rep(c, N) rep(d, N) {
      if (dp[ky][kz][c][d] != 0) trc(L, ky, kz, c + 1, d + 1, dp[ky][kz][c][d]);
    }
    */

    rep(i, N) if (dp[1][1][X][i] != u64{}) die(L);
  }
  die(-1);
}