1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
#include <cstdio>
#include <algorithm>
#include <vector>
#include <stack>

using namespace std;
const int maxn = 200000;
int n, m, d;

struct city {
	int conn_size_cache;
	int valid_conn;
	vector<int> conn;
	bool used;
};

vector<city> cities;
int visit_log[maxn+1];
int visit_log_size = 0;
int visit_best = -1;
int visit_len = 0;

static inline void process_city(const int id)
{
	stack<int> q;
	int log_start = visit_log_size;

	q.push(id);
	cities[id].used = true;

	while(!q.empty()) {
		const int p = q.top();
		q.pop();

		visit_log[visit_log_size++] = p;

		for (int i = 0; i < cities[p].conn_size_cache; i++) {
			const int r = cities[p].conn[i];
			if (! (cities[r].used || cities[r].valid_conn < d)) {
				cities[r].used = true;
				q.push(r);
			}
		}
	}

	if (visit_log_size - log_start > visit_len) {
		visit_best = log_start;
		visit_len = visit_log_size - log_start;
	}
}

static inline void adjust_valid_conns()
{
	stack<int> q;
	for (int i = 0; i < n; i++) {
		if (cities[i].valid_conn < d) {
			cities[i].used = true;
			q.push(i);
		}
	}

	while (!q.empty()) {
		const int c = q.top();
		q.pop();

		for (int i = 0; i < cities[c].conn_size_cache; i++) {
			const int r = cities[c].conn[i];
			cities[r].valid_conn--;
			if (cities[r].valid_conn < d && !cities[r].used) {
				cities[r].used = true;
				q.push(r);
			}
		}
	}

	for (int i = 0; i < n; i++)
		cities[i].used = false;
}

int main()
{

	struct city tmp;
	tmp.conn_size_cache = 0;
	scanf("%d %d %d", &n, &m, &d);

	cities.resize(n);
	for (int i = 0; i < m; i++) {
		int a, b;
		scanf("%d %d", &a, &b);
		a--; b--;
		cities[a].conn.push_back(b);
		cities[b].conn.push_back(a);
	}

	for (int i = 0; i < n; i++) {
		cities[i].conn_size_cache = cities[i].conn.size();
		cities[i].valid_conn = cities[i].conn_size_cache;
		cities[i].used = false;
	}

	adjust_valid_conns();


	for (int i = 0; i < n; i++) {
		if (cities[i].used)
			continue;
		if (cities[i].valid_conn < d) {
			cities[i].used = true;
			continue;
		}

		process_city(i);
	}

	if (visit_best == -1)
		printf("NIE\n");
	else {
		sort(visit_log + visit_best, visit_log + visit_best + visit_len);
		printf("%d\n", visit_len);
		for (int i = 0; i < visit_len; i++)
			printf(i == (visit_len - 1) ? "%d\n" : "%d ", visit_log[visit_best + i] + 1);
	}

	return 0;
}