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

void test_case() {
    int64_t n, m, p;
    cin >> n >> m >> p;
    vector<vector<int64_t>> arr(n+2, vector<int64_t>(m+2));
    vector<int64_t> pre(m+2);
    for (int i = 1; i <= m; i++) {
        arr[n][i] = m-i+1;
        pre[i] = pre[i-1] + arr[n][i];
    }
    for (int k = n-1; k >= 1; k--) {
        int64_t sum = 0;
        for (int i = 1; i <= m; i++) {
            sum += pre[i];
            sum %= p;
        }
        for (int i = 1; i <= m; i++) {
            arr[k][i] = arr[k][i-1] + arr[k+1][i] - arr[k+1][m-i+2];
            arr[k][i] %= p;
        }
        vector<int64_t> b(m+2);
        b[1] = sum;
        for (int i = 2; i <= m; i++) {
            b[i] = b[i-1] - (m-i+2) * arr[k][i-1] - (m-i+1) * arr[k+1][i] + (m-i+1)*arr[k][i];
            b[i] %= p;
        }
        for (int i = 1; i <= m; i++) {
            arr[k][i] = b[i];
        }
        for (int i = 1; i <= m; i++) {
            pre[i] = pre[i-1] + b[i];
            pre[i] %= p;
        }
    }
    int64_t ans = 0;
    for (int i = 1; i <= m; i++) {
        ans = (ans + arr[1][i]) % p;
    }
    if (ans < 0)
        ans += p;
    cout << ans << '\n';
}

void solve() {
    test_case();
}

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);

    solve();

    return 0;
}