oj.uz

답안 #20089

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
20089 2016-02-25T10:49:14 Z hongjun7 트리 (kriii4_X) C++14
100 / 100
 438 ms 11640 KB 
#include <stdio.h>
#include <map>
using namespace std;
const int mod = 1e9 + 7;
int N, M;
map<int, int> par, cnt;
int F(int x) {
	if (!par.count(x)) par[x] = x;
	if (par[x] == x) return x;
	return (par[x] = F(par[x]));
}
int mul(int x, int y) { return (long long)x * y % mod; }
int fm(int x, int y) {
	if (y <= 0) return 1;
	int r = fm(x, y / 2);
	r = mul(r, r);
	if (y % 2 == 1) r = mul(r, x);
	return r;
}
int main() {
	scanf("%d%d", &N, &M);
	bool ok = 1;
	for (int i = 1; i <= M; i++) {
		int x, y; scanf("%d%d", &x, &y);
		int px = F(x), py = F(y);
		if (px == py) ok = 0;
		else par[px] = py;
	}
	int res = 0;
	if (ok) {
		for (auto x : par) cnt[F(x.first)]++;
		res = fm(N, N - par.size() + cnt.size() - 2);
		if (N - par.size() + cnt.size() != 1) for (auto x : cnt) res = mul(res, x.second);
	}
	printf("%d", res);
}

Subtask #1
9.0 / 9.0

# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 1212 KB Output is correct
2 Correct 0 ms 1212 KB Output is correct
3 Correct 0 ms 1212 KB Output is correct
4 Correct 0 ms 1212 KB Output is correct
5 Correct 0 ms 1212 KB Output is correct
6 Correct 0 ms 1212 KB Output is correct
7 Correct 0 ms 1212 KB Output is correct
8 Correct 0 ms 1212 KB Output is correct
9 Correct 0 ms 1212 KB Output is correct
10 Correct 0 ms 1212 KB Output is correct
11 Correct 0 ms 1212 KB Output is correct
12 Correct 0 ms 1212 KB Output is correct
13 Correct 0 ms 1212 KB Output is correct
14 Correct 0 ms 1212 KB Output is correct
15 Correct 0 ms 1212 KB Output is correct
16 Correct 0 ms 1212 KB Output is correct
17 Correct 0 ms 1212 KB Output is correct
18 Correct 0 ms 1212 KB Output is correct
19 Correct 0 ms 1212 KB Output is correct
20 Correct 0 ms 1212 KB Output is correct
21 Correct 0 ms 1212 KB Output is correct
22 Correct 0 ms 1212 KB Output is correct
23 Correct 0 ms 1212 KB Output is correct
24 Correct 0 ms 1212 KB Output is correct
25 Correct 0 ms 1212 KB Output is correct
26 Correct 0 ms 1212 KB Output is correct
27 Correct 0 ms 1212 KB Output is correct
28 Correct 0 ms 1212 KB Output is correct
29 Correct 0 ms 1212 KB Output is correct
30 Correct 0 ms 1212 KB Output is correct

Subtask #2
91.0 / 91.0

# 결과 실행 시간 메모리 Grader output
1 Correct 36 ms 1740 KB Output is correct
2 Correct 85 ms 2400 KB Output is correct
3 Correct 94 ms 2532 KB Output is correct
4 Correct 30 ms 1872 KB Output is correct
5 Correct 62 ms 2268 KB Output is correct
6 Correct 413 ms 10980 KB Output is correct
7 Correct 397 ms 11244 KB Output is correct
8 Correct 393 ms 4248 KB Output is correct
9 Correct 398 ms 11640 KB Output is correct
10 Correct 395 ms 9792 KB Output is correct
11 Correct 373 ms 5568 KB Output is correct
12 Correct 378 ms 5568 KB Output is correct
13 Correct 351 ms 5568 KB Output is correct
14 Correct 365 ms 5568 KB Output is correct
15 Correct 369 ms 5700 KB Output is correct
16 Correct 242 ms 5700 KB Output is correct
17 Correct 255 ms 5700 KB Output is correct
18 Correct 0 ms 1212 KB Output is correct
19 Correct 413 ms 5832 KB Output is correct
20 Correct 415 ms 5832 KB Output is correct
21 Correct 361 ms 5568 KB Output is correct
22 Correct 395 ms 5700 KB Output is correct
23 Correct 420 ms 5964 KB Output is correct
24 Correct 420 ms 5964 KB Output is correct
25 Correct 262 ms 7152 KB Output is correct
26 Correct 255 ms 7152 KB Output is correct
27 Correct 387 ms 9660 KB Output is correct
28 Correct 392 ms 9660 KB Output is correct
29 Correct 438 ms 5832 KB Output is correct
30 Correct 429 ms 5964 KB Output is correct