#include <bits/stdc++.h>
using namespace std;
int n1, n2, m, lev[4010], cur[4010], h[4010], num = 1, T = 4005, du[4010],
                                              K = 0x3f3f3f3f;
vector<int> ans[4010 >> 1];
struct edge {
  int to, next, val;
} data[12100];
inline void add(int x, int y, int val) {
  data[++num].to = y;
  data[num].next = h[x];
  h[x] = num;
  data[num].val = val;
  data[++num].to = x;
  data[num].next = h[y];
  h[y] = num;
  data[num].val = 0;
}
inline bool bfs() {
  queue<int> q;
  memset(lev, 0, sizeof(lev));
  q.push(0);
  lev[0] = 1;
  while (!q.empty()) {
    int x = q.front();
    q.pop();
    for (int i = h[x]; i; i = data[i].next) {
      int y = data[i].to;
      if (lev[y] || !data[i].val) continue;
      lev[y] = lev[x] + 1;
      if (y == T) return 1;
      q.push(y);
    }
  }
  return 0;
}
inline int dinic(int x, int low) {
  if (x == T) return low;
  int tmp = low;
  for (int &i = cur[x]; i; i = data[i].next) {
    int y = data[i].to;
    if (lev[y] != lev[x] + 1 || !data[i].val) continue;
    int res = dinic(y, min(tmp, data[i].val));
    if (!res)
      lev[y] = 0;
    else
      tmp -= res, data[i].val -= res, data[i ^ 1].val += res;
    if (!tmp) return low;
  }
  return low - tmp;
}
int main() {
  cin >> n1 >> n2 >> m;
  for (int i = 1; i <= m; ++i) {
    int x, y;
    cin >> x >> y;
    add(x, y + n1, 1);
    du[x]++;
    du[y + n1]++;
  }
  for (int i = 1; i <= n1 + n2; ++i) K = min(K, du[i]);
  for (int i = 1; i <= n1; ++i)
    if (du[i] > K) add(0, i, du[i] - K);
  for (int i = 1; i <= n2; ++i)
    if (du[i + n1] > K) add(i + n1, T, du[i + n1] - K);
  for (int j = K; j >= 1; --j) {
    while (bfs()) {
      memcpy(cur, h, sizeof(h));
      dinic(0, 0x3f3f3f3f);
    }
    for (int i = 1; i <= m; ++i)
      if (data[i << 1].val) ans[j].push_back(i);
    for (int i = 1; i <= n1; ++i) add(0, i, 1);
    for (int i = 1; i <= n2; ++i) add(i + n1, T, 1);
  }
  puts("0");
  for (int i = 1; i <= K; ++i) {
    printf("%d", ans[i].size());
    for (int j = 0; j < ans[i].size(); ++j) printf(" %d", ans[i][j]);
    puts("");
  }
  return 0;
}
