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#include <iostream>
#include <cstdio>
#include <cstring>
using namespace std;
long long n,k,p;
int main() {
    cin>>n>>k>>p;
    if (n==k) cout<<1<<endl;
    else {
        if (n==k+1) cout<<n%p<<endl;
        else {
            long long ans=1;
            for (int i=1;i<=n;i++){
                ans=(ans*(long long)i)%p;
            }
            cout<<ans<<endl;
        }
    }
    return 0;
}
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