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#include <iostream>

using namespace std;

typedef unsigned long long I;

int n,m;
I p;

#define D(x)

#define MAX 10000010

unsigned w[MAX];
unsigned s[MAX],z[MAX], zz[MAX];

void print(int n) {
    cout << "n: " << n << "------------------\n";
    cout << "s: ";
    for(int i=1;i<=m;i++) {
        cout  << s[i] << " ";
    }
    cout << "\n";
    cout << "z: ";
    for(int i=1;i<=m;i++) {
        cout  << z[i] << " ";
    }
    cout << "\n";
    cout << "zz: ";
    for(int i=1;i<=m;i++) {
        cout  << zz[i] << " ";
    }
    cout << "\n";
    cout << "w: ";
    for(int i=1;i<=m;i++) {
        cout  << w[i] << " ";
    }
    cout << "\n";
}

void f(int n) {
    for(int i=1;i<=m;i++) w[i] = m-i+1;
    D(print(n));
    for(int nn =1;nn<n;nn++) {
        for(int i=1;i<=m;i++)     s[i] =  I(s[i-1] + w[i]) % p;
        for(int i=m;i> 0;i--)     z[i] =  I(z[i+1] + w[i]) % p;
        for(int i=m;i> 0;i--)    zz[i] = I(zz[i+1] + z[i]) % p;
        for(int i=1;i<=m;i++) w[m-i+1] = (I(i)*s[i] + (p - zz[m-i+2])) % p;
        D(print(n));
    }
}


int main()
{
    cin >> n >> m >> p;
    f(n);
    I res = 0;
    for(int i=1;i<=m;i++)     res =  (res + w[i]) % p;
    cout << res << "\n";

}