Cod sursa(job #2254421)
Utilizator | Dobricean Ionut Dobricean_Ioan | Data | 5 octombrie 2018 12:40:17 |
---|---|---|---|
Problema | Colorare3 | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva de probleme | Marime | 0.56 kb |
#include <fstream>
using namespace std;
ifstream fin("colorare3.in");
ofstream fout("colorare3.out");
int n,fii[200001],MOD = 1000000007,k;
int main() {
fin >> n >> k;
for(int i = 1; i < n; i++){
int a, b;
fin >> a >> b;
fii[a]++;
fii[b]++;
}
for(int i = 2; i <= n; i++)
fii[i] --;
long long ans = 1;
for(int j = 1; j <= fii[1]; j++)
ans = (ans * (k - j + 1)) % MOD;
for(int i = 2; i <= n; i++)
for(int j = 1; j <= fii[i]; j++)
ans = (ans * (k - j)) % MOD;
fout << ans;
}