#include <bits/stdc++.h>
using namespace std;
const int N = 300005;
const int P = 1e9 + 7;
const int inf = 1e9;
const long long Inf = 1e15;
inline int IN() {
  char ch = getchar();
  int x = 0, f = 0;
  while (ch < '0' || ch > '9') ch = getchar(), f = (ch == '-');
  while (ch >= '0' && ch <= '9') {
    x = (x << 1) + (x << 3) + ch - 48;
    ch = getchar();
  }
  return f ? (-x) : x;
}
inline int Pow(int x, int y, int p) {
  int an = 1;
  for (; y; y >>= 1, x = (long long)x * x % p)
    if (y & 1) an = (long long)an * x % p;
  return an;
}
void renew(int &x, int y) {
  x += y;
  if (x < 0)
    x += P;
  else if (x >= P)
    x -= P;
}
void setIO(string a) {
  freopen((a + ".in").c_str(), "r", stdin);
  freopen((a + ".out").c_str(), "w", stdout);
}
template <typename T>
inline void chkmin(T &a, const T &b) {
  if (a > b) a = b;
}
template <typename T>
inline void chkmax(T &a, const T &b) {
  if (a < b) a = b;
}
int ux[N], vx[N], n, m;
struct edge {
  int v, id, pre;
} e[N * 2];
int dex, adj[N];
int gtw[N], deg[N], vis[N];
void dfs(int x, int par) {
  vis[x] = 1;
  for (int i = adj[x]; i; i = e[i].pre) {
    int v = e[i].v;
    if (vis[v]) continue;
    dfs(v, x);
    if (deg[v]) {
      int id = e[i].id;
      deg[v] ^= 1;
      deg[x] ^= 1;
      gtw[id] ^= 1;
    }
  }
}
vector<int> bel[N];
int main() {
  scanf("%d%d", &n, &m);
  for (int i = (int)1; i <= (int)m; i++) {
    scanf("%d%d", ux + i, vx + i);
    e[++dex] = (edge){vx[i], i, adj[ux[i]]};
    adj[ux[i]] = dex;
    e[++dex] = (edge){ux[i], i, adj[vx[i]]};
    adj[vx[i]] = dex;
    gtw[i] = 0;
    deg[ux[i]] ^= 1;
  }
  for (int i = (int)1; i <= (int)n; i++)
    if (!vis[i]) dfs(i, 0);
  int ans = m;
  for (int i = (int)1; i <= (int)n; i++)
    if (deg[i]) ans--;
  ans /= 2;
  printf("%d\n", ans);
  for (int i = (int)1; i <= (int)m; i++) {
    if (!gtw[i])
      bel[ux[i]].push_back(vx[i]);
    else
      bel[vx[i]].push_back(ux[i]);
  }
  for (int i = (int)1; i <= (int)n; i++) {
    for (int j = 0; j + 1 < bel[i].size(); j += 2) {
      int u = bel[i][j];
      int v = bel[i][j + 1];
      printf("%d %d %d\n", u, i, v);
    }
  }
  return 0;
}
