Cod sursa(job #3289116)
| Utilizator | Data | 25 martie 2025 18:39:19 | |
|---|---|---|---|
| Problema | Dirichlet | Scor | 100 |
| Compilator | cpp-64 | Status | done |
| Runda | Arhiva de probleme | Marime | 0.55 kb |
#include <fstream>
using namespace std;
ifstream fin("dirichlet.in");
ofstream fout("dirichlet.out");
const int MOD=9999991;
long long pow(long long a, long long b)
{
if (b==1)
return a;
if (b%2==0)
return pow(a,b/2)*pow(a,b/2)%MOD;
else
return (a*pow(a,b/2)%MOD)*pow(a,b/2)%MOD;
}
int main()
{
long long n,n2,a=1,b=1,i;
fin>>n;
n2=2*n;
for(i=2;i<=n;i++)
a=(a*i)%MOD;
for (i=n+2;i<=n2;i++)
b=b*i%MOD;
fout<<(b*pow(a,MOD-2)%MOD)%MOD<<'\n';
return 0;
}
