Cod sursa(job #2221994)
Utilizator | Data | 16 iulie 2018 12:01:41 | |
---|---|---|---|
Problema | Dirichlet | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva de probleme | Marime | 0.54 kb |
#include <fstream>
using namespace std;
const int MOD = 9999991;
ifstream in("dirichlet.in");
ofstream out("dirichlet.out");
long long pow(long long a, int b) {
long long p = 1;
while(b) {
if(b & 1)
p = p * a % MOD;
a = a * a % MOD;
b >>= 1;
}
return p;
}
int main()
{
int n;
in >> n;
long long a = 1, b = 1;
for(int i = 2; i <= n; i++) {
a = a* (n+i) % MOD;
b = b * i % MOD;
}
out << a * pow(b, MOD-2) % MOD;
return 0;
}