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#include <bits/stdc++.h>
#define dbg(x) " [" << #x << ": " << (x) << "] "
using namespace std;
template<typename A,typename B>
ostream& operator<<(ostream& out,const pair<A,B>& p) {
    return out << "(" << p.first << ", " << p.second << ")";
}
template<typename T>
ostream& operator<<(ostream& out,const vector<T>& c) {
    out << "{";
    for(auto it = c.begin(); it != c.end(); it++) {
        if(it != c.begin()) out << ", ";
        out << *it;
    }
    return out << "}";
}
const int mod = 1e9 + 7;
long long ans = 0;
int n,m;
vector<int> v;
void check() {
    vector<vector<int>> dp(n + 1,vector<int>(n + 1));
    for(int i = n; i >= 1; i--) {
        for(int j = i + 1; j <= n; j++) {
            if(v[i - 1] == v[j - 1]) {
                dp[i][j] = 1;
            } else {
                for(int k = i + 1; k < j; k++) {
                    if(dp[i][k - 1] && dp[k][j]) {
                        dp[i][j] = 1;
                        break;
                    }
                }
            }
        }
    }
    if(dp[1][n]) {
        ans++;
        if(ans == mod) {
            ans = 0;
        }
    }
}
void rec(int id) {
    if(id == n) {
        check();
        return;
    }
    for(int i = 1; i <= m; i++) {
        v[id] = i;
        rec(id + 1);
    }
}
void solve() {
    cin >> n >> m;
    v.resize(n);
    v[0] = 1;
    rec(1);
    cout << (ans * m) % mod << endl;
}
int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    int testNum = 1;
    //cin >> testNum;
    for(int i = 1; i <= testNum; i++) {
        solve();
    }
    return 0;
}