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
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.util.LinkedList;
import java.util.StringTokenizer;


/**
 * @author tzmarz
 * @since 30 wrz 2015
 */
public class mis {
	
	
	private int					N;
	private City[]				cities;
	private int					minRoads;
	private LinkedList<City>	q;
	private int[]				clickRepr;
	private int[]				clickSize;
	
	
	public mis() {
	
		readInput();
		
		for (City c : cities)
			if (c.roadCnt < minRoads) {
				q.add(c);
				c.inQ = false;
			}
		
		while (!q.isEmpty()) {
			handle(q.removeFirst());
		}
		
		clickRepr = new int[N];
		clickSize = new int[N];
		for (int i = 0; i < N; ++i)
			clickRepr[i] = -1;
		for (int i = 0; i < N; ++i)
			if (cities[i].championship)
				markClick(i, i);
		
		int largestClick = 0;
		for (int i = 0; i < N; ++i)
			if (clickSize[i] > clickSize[largestClick])
				largestClick = i;
		
		if (clickSize[largestClick] == 0)
			Writer.print("NIE\n");
		else
			printClick(largestClick);
	}
	
	private void printClick(int largestClick) {
	
		Writer.print("" + clickSize[largestClick] + "\n");
		for (int i = 0; i < N; ++i)
			if (clickRepr[i] == largestClick)
				Writer.print("" + (i + 1) + " ");
		Writer.println();
	}
	
	
	private void markClick(int repr, int city) {
	
		if (clickRepr[city] != -1)
			return;
		
		clickRepr[city] = repr;
		clickSize[repr]++;
		for (Road r = cities[city].first; r != null; r = r.next)
			markClick(repr, r.to.nr);
	}
	
	private void handle(City city) {
	
		assert (city.roadCnt < minRoads);
		
		city.championship = false;
		
		for (Road r = city.first; r != null; r = r.next) {
			City B = r.to;
			B.roadCnt--;
			if (!B.inQ && B.roadCnt < minRoads) {
				B.inQ = true;
				q.addLast(B);
			}
			
			Road BA = r.sibling;
			Road prev = BA.prev;
			Road next = BA.next;
			
			// prev -> next
			if (prev != null)
				prev.next = next;
			else
				B.first = next;
			
			// prev <- next
			if (next != null)
				next.prev = prev;
			else
				;
			
		}
		
		city.inQ = false;
	}
	
	private void readInput() {
	
		N = Reader.nextInt();
		
		int nRoads = Reader.nextInt();
		minRoads = Reader.nextInt();
		
		
		cities = new City[N];
		for (int i = 0; i < N; ++i) {
			cities[i] = new City();
			cities[i].nr = i;
		}
		
		for (int i = 0; i < nRoads; ++i) {
			int a = Reader.nextInt() - 1;
			int b = Reader.nextInt() - 1;
			
			City A = cities[a];
			A.nr = a;
			City B = cities[b];
			B.nr = b;
			
			Road AB = new Road();
			AB.next = A.first;
			A.first = AB;
			if (AB.next != null)
				AB.next.prev = AB;
			
			Road BA = new Road();
			BA.next = B.first;
			B.first = BA;
			if (BA.next != null)
				BA.next.prev = BA;
			
			AB.from = BA.to = A;
			AB.to = BA.from = B;
			
			AB.sibling = BA;
			BA.sibling = AB;
			
			A.roadCnt++;
			B.roadCnt++;
		}
		
		q = new LinkedList<City>();
	}
	
	
	
	class Road {
		
		City	from, to;
		Road	next, prev, sibling;
		
		public String toString() {
		
			return "" + from.nr + "->" + to.nr;
		}
	}
	
	class City {
		
		int		nr;
		int		roadCnt;
		Road	first;
		boolean	championship	= true;
		boolean	inQ				= false;
		
		public String toString() {
		
			return "" + nr + ": roadCnt=" + roadCnt;
		}
	}
	
	
	
	/****************** MAIN ******************/
	public static void main(String[] args) throws FileNotFoundException {
	
		Reader.init(System.in);
		new mis();
		Writer.flush();
	}
	
	// =========================
	// based on @author: http://www.rgagnon.com/javadetails/java-0603.html
	static class Writer {
		
		private static BufferedWriter	out;
		
		static {
			out = new BufferedWriter(new OutputStreamWriter(System.out), 512);
		}
		
		static void print(char c) {
		
			try {
				out.write(c);
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
		
		static void print(String str) {
		
			try {
				out.write(str);
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
		
		static void println() {
		
			try {
				out.write("\n");
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
		
		static void flush() {
		
			try {
				out.flush();
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
		
		@Override
		protected void finalize() {
		
			try {
				out.flush();
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
	}
	
	// =========================
	// based on @author: http://www.cpe.ku.ac.th/~jim/java-io.html
	static class Reader {
		
		static BufferedReader	reader;
		static StringTokenizer	tokenizer;
		
		static void init(InputStream input) {
		
			reader = new BufferedReader(new InputStreamReader(input));
			tokenizer = new StringTokenizer("");
		}
		
		static String next() {
		
			try {
				while (!tokenizer.hasMoreTokens()) {
					String str;
					str = reader.readLine();
					if (str == null)
						return null;
					tokenizer = new StringTokenizer(str);
				}
			} catch (IOException e) {
				e.printStackTrace();
			}
			return tokenizer.nextToken();
		}
		
		static int nextInt() {
		
			try {
				return Integer.parseInt(next());
			} catch (NumberFormatException e) {
				e.printStackTrace();
			}
			return -1;
		}
		
		static double nextDouble() {
		
			try {
				return Double.parseDouble(next());
			} catch (NumberFormatException e) {
				e.printStackTrace();
			}
			return -1;
		}
	}
	// =========================
	
	
	
}