#include <bits/stdc++.h>
using namespace std;
long long fact_rec (int n)
{
if (n <= 1)
return 1;
else return n * fact_rec (n - 1);
}
long long fact_dp (int n)
{
long long facts[n + 1];
facts[0] = 1;
for (int i = 1; i <= n; ++i)
facts[i] = facts[i - 1] * i;
return facts[n];
}
int main ()
{
cout << fact_dp (80);
}
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