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#include<bits/stdc++.h>
using namespace std;
template <typename A, typename B>
string to_string(pair<A, B> p);
 
template <typename A, typename B, typename C>
string to_string(tuple<A, B, C> p);
 
template <typename A, typename B, typename C, typename D>
string to_string(tuple<A, B, C, D> p);
 
string to_string(const string& s) {
  return '"' + s + '"';
}
 
string to_string(const char* s) {
  return to_string((string) s);
}
 
string to_string(bool b) {
  return (b ? "true" : "false");
}
 
string to_string(vector<bool> v) {
  bool first = true;
  string res = "{";
  for (int i = 0; i < static_cast<int>(v.size()); i++) {
    if (!first) {
      res += ", ";
    }
    first = false;
    res += to_string(v[i]);
  }
  res += "}";
  return res;
}
 
template <size_t N>
string to_string(bitset<N> v) {
  string res = "";
  for (size_t i = 0; i < N; i++) {
    res += static_cast<char>('0' + v[i]);
  }
  return res;
}
 
template <typename A>
string to_string(A v) {
  bool first = true;
  string res = "{";
  for (const auto &x : v) {
    if (!first) {
      res += ", ";
    }
    first = false;
    res += to_string(x);
  }
  res += "}";
  return res;
}
 
template <typename A, typename B>
string to_string(pair<A, B> p) {
  return "(" + to_string(p.first) + ", " + to_string(p.second) + ")";
}
 
template <typename A, typename B, typename C>
string to_string(tuple<A, B, C> p) {
  return "(" + to_string(get<0>(p)) + ", " + to_string(get<1>(p)) + ", " + to_string(get<2>(p)) + ")";
}
 
template <typename A, typename B, typename C, typename D>
string to_string(tuple<A, B, C, D> p) {
  return "(" + to_string(get<0>(p)) + ", " + to_string(get<1>(p)) + ", " + to_string(get<2>(p)) + ", " + to_string(get<3>(p)) + ")";
}
 
void debug_out() { cerr << endl; }
 
template <typename Head, typename... Tail>
void debug_out(Head H, Tail... T) {
  cerr << " " << to_string(H);
  debug_out(T...);
}
 
#if 0
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
#else
#define debug(...) 42
#endif
#define int long long
int n,m,p;
int32_t main(){
	cin >>n >>m >>p;
	vector<int> up(m+1),down(m+1);
	for(int i=0;i<m+1;i++){
		if(i==0){
			down[i]=0;
		}
		else{
			down[i]=down[i-1]+i;
			down[i]%=p;
		}
		up[m-i]=down[i];
	}
	for(int i=1;i<n;i++){
		int all=down.back();
		vector<int> ndown(m+1);
		int pref=0;
		for(int j=1;j<=m;j++){
			ndown[j]=ndown[j-1];
			/*for(int k=0;k<j;k++){
				int here=all-down[k]-up[j];
				debug(here);
				ndown[j]+=here;
			}*/
			ndown[j]+=all*j-up[j]*j-pref;
			ndown[j]%=p;
			if(ndown[j]<0)ndown[j]+=p;
			pref+=down[j];
			pref%=p;
		}
		
		for(int j=0;j<=m;j++){
			down[j]=ndown[j];
			up[m-j]=ndown[j];
		}
	}
	cout <<down.back()%p;
}