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#include<bits/stdc++.h>
#define fi first
#define se second
#define pb push_back
using namespace std;

long long dp[3009];
const long long M = 1e9 + 7;

int main()
{
	ios_base::sync_with_stdio(false);
	cin.tie(0);
	cout.tie(0);
	long long n, m, a = 1, b, c;
	cin>>n>>m;
	dp[1] = 0;
	dp[2] = 1;
	for(int i=3; i<=n; i++)
	{
		a = (a * m) % M;
		b = 0;
		for(int j=2; j<=i-2; j++)
		{
			c = (dp[j] * dp[i-j]) % M;
			b = (b + c) % M;
		}
		dp[i] = ((m - 1) * b) % M;
		dp[i] = (dp[i] + a) % M;
	}
	cout<<(dp[n] * m) % M;
	return 0;
}