Cod sursa(job #2506944)
Utilizator | cotiga david davidcotiga | Data | 9 decembrie 2019 08:49:28 |
---|---|---|---|
Problema | Dirichlet | Scor | 100 |
Compilator | cpp-64 | Status | done |
Runda | Arhiva de probleme | Marime | 0.56 kb |
#include <fstream>
using namespace std;
ifstream cin("dirichlet.in");
ofstream cout("dirichlet.out");
const int MOD = 9999991;
long long power(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()
{
long long a = 1, b = 1, n, i;
cin >> n;
for(i = 2; i <= n; i++){
a = a * (n + i) % MOD;
b = b * i % MOD;
}
cout << a * power(b, MOD - 2) % MOD;
return 0;
}