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

const int INF = 1000LL * 1000 * 1000 * 1000 * 1000 * 1000;

int p;
int addd (int a, int b) {
    return ((a + b) % p + p) % p;
}
int multi (int a, int b) {
    return ((a * b) % p + p) % p;
}
signed main() {
    int n, m;
    cin >> n >> m >> p;
    vector <vector <int>> dp(n, vector<int>(m));
    vector <vector <int>> dp2(n, vector<int>(m));
    for (int i = 0; i < m; i++) {
        dp[0][i] = i + 1;
    }
    for (int i = 1; i < m; i++) {
        dp[0][i] = addd(dp[0][i], dp[0][i - 1]);
    }
    dp2[0][0] = dp[0][0];
    for (int i = 1; i < m; i++) {
        dp2[0][i] = addd(dp[0][i], dp[0][i - 1]);
    }
    for (int j = 0; j < m; j++) {
        
        cerr << dp[0][j] << " ";
    }
    cerr << endl;
    for (int j = 0; j < m; j++) {
        
        cerr << dp2[0][j] << " ";
    }
    cerr << endl;
    for (int i = 1; i < n; i++) {
        for (int j = 0; j < m; j++) {
            dp[i][j] = multi(dp[i - 1][m - 1], (j+1));
            if (j < m - 1) {
                dp[i][j] = addd(dp[i][j], -1LL * multi((j+1), dp[i - 1][m - j  - 2]));
            }
            if (j > 0) {
                dp[i][j] = addd(dp[i][j], -1LL * dp2[i - 1][j - 1]);
            }
            // if (j == m - 1) {
            //     dp[i][j] = 0;
            //     dp[i][j] = multi(dp[0][j], dp[i - 1][j]);
            //     dp[i][j] = addd(dp[i][j], multi(-2LL, dp2[i - 1][j - 1]));
            // }
        }
        for (int j = 0; j < m; j++) {
            cerr << dp[i][j] << " ";
        }
        cerr << endl;
        for (int j = 1; j < m ; j++) {
            dp[i][j] = addd(dp[i][j], dp[i][j - 1]);
        }
        dp2[i][0] = dp[i][0];
        for (int j = 1; j < m; j++) {
            dp2[i][j] = addd(dp[i][j], dp[i][j - 1]);
        }
    }
    cout << dp[n - 1][m - 1] << endl;
    return 0;
}