#include <bits/stdc++.h>
using namespace std;
template <typename T>
void maxtt(T& t1, T t2) {
  t1 = max(t1, t2);
}
template <typename T>
void mintt(T& t1, T t2) {
  t1 = min(t1, t2);
}
bool debug = 0;
int n, m, k;
int dx[4] = {0, 1, 0, -1}, dy[4] = {1, 0, -1, 0};
string direc = "URDL";
long long ln, lk, lm;
void etp(bool f = 0) {
  puts(f ? "YES" : "NO");
  exit(0);
}
void addmod(int& x, int y, int mod = 998244353) {
  assert(y >= 0);
  x += y;
  if (x >= mod) x -= mod;
  assert(x >= 0 && x < mod);
}
void et(int x = -1) {
  printf("%d\n", x);
  exit(0);
}
long long fastPow(long long x, long long y, int mod = 998244353) {
  long long ans = 1;
  while (y > 0) {
    if (y & 1) ans = (x * ans) % mod;
    x = x * x % mod;
    y >>= 1;
  }
  return ans;
}
long long gcd1(long long x, long long y) { return y ? gcd1(y, x % y) : x; }
int a[100035], b[100035], fr[100035], to[100035], S;
pair<int, int> sp[100035];
vector<int> seq[100035];
bool vis[100035];
void mov(int x, int y, int s) {
  vector<int> tmp;
  for (int z : seq[y]) vis[z] = 1;
  while (s) {
    int t = seq[x].back();
    seq[x].pop_back();
    if (vis[t]) {
      tmp.push_back(t);
      continue;
    }
    vis[t] = 1;
    seq[y].push_back(t);
    s--;
    printf("%d %d %d\n", x, y, t);
  }
  for (int z : seq[y]) vis[z] = 0;
  for (int z : tmp) seq[x].push_back(z);
}
void fmain(int tid) {
  scanf("%d%d", &n, &m);
  for (int(i) = 1; (i) <= (int)(n); (i)++) {
    sp[i].second = i;
    scanf("%d", &fr[i]);
    sp[i].first = -fr[i];
    seq[i].resize(fr[i]);
    S += fr[i];
    for (int(j) = 1; (j) <= (int)(fr[i]); (j)++) {
      scanf("%d", &seq[i][j - 1]);
    }
  }
  sort(sp + 1, sp + 1 + n);
  for (int(i) = 1; (i) <= (int)(n); (i)++) to[i] = S / n + (S % n >= i);
  int ans = 0;
  for (int(i) = 1; (i) <= (int)(n); (i)++)
    ans += max(0, to[i] - fr[sp[i].second]);
  printf("%d\n", ans);
  for (int i = 1, j = n; i < j;) {
    int x = sp[i].second, y = sp[j].second;
    if (fr[x] == to[i]) {
      i++;
      continue;
    }
    if (fr[y] == to[j]) {
      j--;
      continue;
    }
    int s = min(abs(fr[x] - to[i]), abs(fr[y] - to[j]));
    fr[x] -= s;
    fr[y] += s;
    mov(x, y, s);
  }
}
int main() {
  int t = 1;
  for (int(i) = 1; (i) <= (int)(t); (i)++) {
    fmain(i);
  }
  return 0;
}
