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#include <bits/stdc++.h>
using namespace std;

#define pb push_back
#define eb emplace_back
#define mp make_pair
#define ll long long
#define ull unsigned long long
//#define int LL
#define FOR(i,a,b) for(int i = (a); i <= (b); i++)
#define REP(i,n) FOR(i,0,(int)(n)-1)
#define VI vector<int>
#define VVI vector<VI>
#define PII pair<int, int>
#define PLL pair<ll, ll>
#define st first
#define nd second
#define ALL(x) (x).begin(), (x).end()
#define SZ(x) ((int)x.size())

template<class C> void mini(C& x, C y) { x = min(x,y); }
template<class C> void maxi(C& x, C y) { x = max(x,y); }

template<class TH> void _dbg(const char *sdbg, TH h){ cerr<<sdbg<<'='<<h<<endl; }
template<class TH, class... TA> void _dbg(const char *sdbg, TH h, TA... a) {
	while(*sdbg!=',') cerr<<*sdbg++;
	cerr<<'='<<h<<','; _dbg(sdbg+1, a...);
}

template<class T> ostream &operator<<(ostream& os, vector<T> V) {
	os << "["; for (auto vv : V) os << vv << ","; return os << "]";
}
template<class L, class R> ostream &operator<<(ostream &os, pair<L,R> P) {
	return os << "(" << P.st << "," << P.nd << ")";
}

#ifdef LOCAL
#define debug(...) _dbg(#__VA_ARGS__, __VA_ARGS__)
#else
#define debug(...) (__VA_ARGS__)
#define cerr if(0)cout
#endif

int solve(int n, int m) {
	int res = 0;

	VI start = {};

	function<bool(int)> is_ok = [&](int i) {
		if(i >= n-1) return false;
		if(start[i] == start.back()) return true;

		int pocz = start[i];

		while(++i < n) {
			if(start[i] != pocz) continue;
			if(is_ok(i+1)) return true;
		}

		return false;
	};

	auto check = [&]() -> int {
		return is_ok(0) ? 1 : 0;
	};

	function<void()> recurse = [&]() {
		if(SZ(start) == n) { 
			res += check();
			return;
		}

		REP(i, m) {
			start.push_back(i);
			recurse();
			start.pop_back();
		}
	};

	recurse();
	
	return res;
}

const int MAXN = 3005;
const ll mod = 1e9+7;
typedef vector<ll> Poly;

ll linearRec(Poly S, Poly tr, ll k) {
	int n = SZ(tr);
	auto combine = [&](Poly a, Poly b) {
		Poly res(n * 2 + 1);
		FOR(i,0,n) FOR(j,0,n)
			res[i + j] = (res[i + j] + a[i] * b[j]) % mod;
		for (int i = 2 * n; i > n; --i) REP(j,n)
			res[i - 1 - j] = (res[i - 1 - j] + res[i] * tr[j]) % mod;
		res.resize(n + 1);
		return res;
	};

	Poly pol(n + 1), e(pol);
	pol[0] = e[1] = 1;

	for (++k; k; k /= 2) {
		if (k % 2) pol = combine(pol, e);
		e = combine(e, e);
	}

	ll res = 0;
	REP(i,n) res = (res + pol[i + 1] * S[i]) % mod;
	return res;
}

ll modpow(ll b, ll e) {
	ll ans = 1;
	for (; e; b = b * b % mod, e /= 2)
		if (e & 1) ans = ans * b % mod;

	return ans;
}

ll inverse(ll x) {
	return modpow(x, mod-2);
}

ll fact[MAXN];
ll fact_i[MAXN];

void init() {
	fact[0] = 1;
	FOR(i, 1, MAXN-1) {
		fact[i] = (fact[i-1] * i) % mod;
		fact_i[i] = inverse(fact[i]);
		//if(i < 10) debug(fact[i]);
	}
}

int n,m;

signed main() {
	ios_base::sync_with_stdio(false); cin.tie(nullptr);

	//init();
	cin >> n >> m;

	cout << solve(n, m);

	return 0;
}