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
//============================================================================
// Name        : potyczki2015.cpp
// Author      : Hanczar
// Version     :
// Copyright   : Your copyright notice
// Description : Hello World in C++, Ansi-style
//============================================================================

#include <cstdio>
#include <stdint.h>
#include <vector>
#include <queue>
#include <algorithm>
using namespace std;


#define DEBUG 0

#define hassert(x)  if (DEBUG && !(x)){printf("ASSSERT:%d",__LINE__);fflush(stdout);*((int*)NULL)=0;}

static int d;
static queue<int> checkNotSCities;
static queue<int> connections;

static int largestgroup_id   = 0;
static int largestgroup_size = 0;
class City {
  vector<int> roads;
public:
  static vector<City> cities;
  int id;
  bool removed;
  int roadcount;
  static int removedCnt;
  bool marked;
  int citygroup;
  int citygroupsize;


  City() :
      removed(false), roadcount(0),marked(false),citygroup(0),citygroupsize(0) {
  }
  void addRoad(int v1) {
    roads.push_back(v1);
    roadcount++;
  }

  void removeFromS() {
    if (!removed) {
      removed = true;
      removedCnt++;
      for (int i = 0; i < roads.size(); i++) {
        int cidx = roads[i];
        City &c = cities[cidx];
        if (!c.removed) {
          c.roadcount--;
          if (c.roadcount < d && !c.marked) {
            c.marked = true;
            checkNotSCities.push(cidx);
          }
        }
      }
    } else {
      if (DEBUG)printf("removing ignored\n");
    }
  }

  void addConnectionTown() {
    if (++citygroupsize > largestgroup_size) {
      largestgroup_size = citygroupsize;
      largestgroup_id= citygroup;
    }
  }

  void connect() {
    hassert(!removed);
    for (int i=0;i<roads.size() ;i++) {
      int cidx = roads[i];
      City &c = cities[cidx];
      if (!c.removed) {
        hassert(c.citygroup == citygroup || c.citygroup == 0 );
        if (c.citygroup == 0) {
          c.citygroup = citygroup;
          cities[citygroup].addConnectionTown();
          c.connect();
        }
      }
    }
  }
};

vector<City> City::cities;
int City::removedCnt = 0;

int main() {
  int n, m;

  scanf("%d %d %d", &n, &m, &d);
  n++; //0 element
  City::cities.resize(n);
  for (int i = 0; i < m; i++) {
    int v1, v2;
    scanf("%d %d", &v1, &v2);
    City::cities[v1].addRoad(v2);
    City::cities[v2].addRoad(v1);
  }

  for (int i = 0; i < n; i++) {
    City::cities[i].id = i;
    if (City::cities[i].roadcount < d) {
      if (DEBUG)
        printf("remove %d rc:%d  d:%d\n", i, City::cities[i].roadcount, d);
      City::cities[i].removeFromS();
    }
  }

  while (!checkNotSCities.empty()) {
    int idx = checkNotSCities.front();
    City &c = City::cities[idx];
    checkNotSCities.pop();
    if (DEBUG)
      printf(" -- remove by queue %d\n", idx);
    c.removeFromS();
  }

  if (DEBUG)
    printf("result  %d   %d\n", n, City::removedCnt);

  // choose the biggest city group
  for (int i=1;i<n;i++) {
    City &c = City::cities[i];
    if (0==c.citygroup && !c.removed) {
      c.citygroup = i;
      c.citygroupsize+=1;
      c.connect();
    }
  }

  int result = largestgroup_size;
  if (0 == result) {
    printf("NIE\n");
  } else {
    printf("%d\n", largestgroup_size);
    for (int i = 0; i < n; i++) {
      if (City::cities[i].citygroup == largestgroup_id) {
        printf("%d ", i);
      }
    }
  }
  printf("\n");

  return 0;
}