#include <bits/stdc++.h>
using namespace std;
#include <atcoder/modint>
using namespace atcoder;
//using mint = modint998244353;
using mint = modint1000000007;
using ll = long long;
using ld = long double;
using pll = pair<ll, ll>;
using tlll = tuple<ll, ll, ll>;
constexpr ll INF = 1LL << 60;
template<class T> bool chmin(T& a, T b) {if (a > b) {a = b; return true;} return false;}
template<class T> bool chmax(T& a, T b) {if (a < b) {a = b; return true;} return false;}
ll safemod(ll A, ll M) {return (A % M + M) % M;}
ll divfloor(ll A, ll B) {if (B < 0) {return divfloor(-A, -B);} return (A - safemod(A, B)) / B;}
ll divceil(ll A, ll B) {if (B < 0) {return divceil(-A, -B);} return divfloor(A + B - 1, B);}
template<class T> void unique(vector<T> &V) {V.erase(unique(V.begin(), V.end()), V.end());}
template<class T> void sortunique(vector<T> &V) {sort(V.begin(), V.end()); V.erase(unique(V.begin(), V.end()), V.end());}
#define FINALANS(A) do {cout << (A) << '\n'; exit(0);} while (false)
template<class T> void printvec(vector<T> &V) {int N = V.size(); for (int i = 0; i < N; i++) cout << V[i] << (i == N - 1 ? '\n' : ' ');}
template<class T> void printvect(vector<T> &V) {for (auto v : V) cout << v << '\n';}
template<class T> void printvec2(vector<vector<T>> &V) {for (auto &v : V) printvec(v);}

class mintcombination
{
public:
  vector<mint> fac, finv, inv;

  mintcombination(ll M)
  {
    fac.resize(M + 1);
    finv.resize(M + 1);
    inv.resize(M + 1);

    fac.at(0) = 1, finv.at(0) = 1;
    fac.at(1) = 1, finv.at(1) = 1, inv.at(1) = 1;

    for (ll i = 2; i <= M; i++)
    {
      fac.at(i) = fac.at(i - 1) * i;
      inv.at(i) = mint::mod() - inv.at(mint::mod() % i) * (mint::mod() / i);
      finv.at(i) = finv.at(i - 1) * inv.at(i);
    }
  }

  mint P(ll N, ll K)
  {
    if (N < K) return 0;
    if (N < 0 || K < 0) return 0;
    return fac.at(N) * finv.at(N - K);
  }

  mint C(ll N, ll K)
  {
    if (N < K) return 0;
    if (N < 0 || K < 0) return 0;
    return fac.at(N) * finv.at(K) * finv.at(N - K);
  }

  mint H(ll N, ll K)
  {
    return C(N + K - 1, K);
  }
};

int main()
{
  // https://oeis.org/A183109

  ll H, W;
  cin >> H >> W;

  if (H > W)
    swap(H, W);

  mintcombination com(H);

  mint ans = 0;
  for (ll i = 0; i <= H; i++)
  {
    mint tmp = (i % 2 == 0 ? 1 : -1) * com.C(H, i) * (mint(2).pow(H - i) - 1).pow(W);
    ans += tmp;
  }
  cout << ans.val() << endl;
}