Submission #19676

#	Time	Username	Problem	Language	Result	Execution time	Memory
19676		hongjun7	트리 (kriii4_X)	C++98	9 / 100	97 ms	1084 KiB

X

#include <stdio.h>
#include <algorithm>
using namespace std;
int n, m, par[10], a[10], b[10], c[10], res;
void f(int x) {
	c[x] = 1;
	for (int i = 1; i <= n; i++) {
		if (par[i] == x) {
			f(i);
		}
	}
}
void go(int x) {
	if (x == n + 1) {
		for (int i = 1; i <= n; i++) c[i] = 0;
		f(1);
		bool ok = 1;
		for (int i = 1; i <= n; i++) if (c[i] == 0) ok = 0;
		for (int i = 1; i <= m; i++) if (!(par[a[i]] == b[i] || par[b[i]] == a[i])) ok = 0;
		if (ok) res++;
		return;
	}
	if (x == 1) {
		par[x] = 0;
		go(x + 1);
	}
	else {
		for (int i = 1; i <= n; i++) {
			if (i == x) continue;
			par[x] = i;
			go(x + 1);
		}
	}
}
int main() {
	scanf("%d%d", &n, &m);
	for (int i = 1; i <= m; i++) scanf("%d%d", &a[i], &b[i]);
	res = 0;
	go(1);
	printf("%d", res);
}

• Subtask 1: 9 / 9
• Subtask 2: 0 / 91