#include <bits/stdc++.h>
using namespace std;
//@formatter:off
using ll = long long;
template<typename T> istream &operator>>(istream &is, vector<T> &a);
template<typename T> ostream &operator<<(ostream &os, vector<T> &a);
//@formatter:on
struct Hash {
int n;
const int p = 237, mod = 1e9 + 21;
vector<int> hash, pw;
int sum(int a, int b) {
if (a + b >= mod) return a + b - mod;
else return a + b;
}
int sub(int a, int b) {
if (a - b < 0)
return a - b + mod;
else
return a - b;
}
int mul(int a, int b) {
return 1ll * a * b % mod;
}
int get(int l, int r) {
return sub(hash[r], mul(hash[l], pw[r - l]));
}
Hash(string s) {
n = s.size();
hash.resize(n + 1);
pw.resize(n + 1);
pw[0] = 1;
for (int i = 0; i < n; ++i) {
pw[i + 1] = mul(pw[i], p);
}
for (int i = 0; i < n; ++i) {
hash[i + 1] = sum(mul(hash[i], p), s[i] % mod);
}
}
};
struct node {
array<int, 26> nx;
int suff, prev;
ll cnt;
node() {
nx.fill(-1);
suff = prev = -1;
cnt = 0;
}
};
struct Suff {
int a = 0;
vector<ll> cnt;
vector<int> term;
vector<node> S;
Suff() {
S.emplace_back();
cnt.emplace_back();
S[0].cnt = 1;
}
void add(int x) {
int b = S.size();
S.emplace_back();
cnt.emplace_back();
S[b].prev = a;
S[b].suff = 0;
for (; a != -1; a = S[a].suff) {
if (S[a].nx[x] == -1) {
S[a].nx[x] = b;
S[b].cnt += S[a].cnt;
continue;
}
int c = S[a].nx[x];
if (S[c].prev == a) {
S[b].suff = c;
break;
}
int d = S.size();
S.emplace_back();
cnt.emplace_back();
S[d].suff = S[c].suff;
S[c].suff = S[b].suff = d;
S[d].prev = a;
S[d].nx = S[c].nx;
for (; a != -1 && S[a].nx[x] == c; a = S[a].suff) {
S[d].cnt += S[a].cnt;
S[c].cnt -= S[a].cnt;
S[a].nx[x] = d;
}
break;
}
a = b;
}
void init() {
term.resize((int) S.size());
int v = a;
while (v != -1) {
term[v] = true;
v = S[v].suff;
}
dfs(0);
}
void dfs(int v) {
cnt[v] = term[v];
for (int i = 0; i < 26; i++) {
if (S[v].nx[i] == -1) continue;
if (cnt[S[v].nx[i]] == 0) dfs(S[v].nx[i]);
cnt[v] += cnt[S[v].nx[i]];
}
}
int move(string s) {
int v = 0;
for (auto ch: s) {
if (S[v].nx[ch - 'a'] == -1) return -1;
v = S[v].nx[ch - 'a'];
}
return v;
}
};
signed main() {
#ifdef LOCAL
freopen("input.txt", "r", stdin);
freopen("output.txt", "w", stdout);
#else
ios_base::sync_with_stdio(false);
cin.tie(0);
#endif
int n, m;
cin >> n >> m;
vector<vector<int>> g(n);
for (int i = 0; i < m; ++i) {
int u, v;
cin >> u >> v;
g[u - 1].push_back(v - 1);
g[v - 1].push_back(u - 1);
}
vector<int> ord(n);
std::iota(ord.begin(), ord.end(), 0);
std::sort(ord.begin(), ord.end(), [&](int i, int j) {
return g[i].size() > g[j].size();
});
for (int v = 0; v < n; ++v) {
std::sort(g[v].begin(), g[v].end(), [&](int i, int j) {
return g[i].size() < g[j].size();
});
while (!g[v].empty() && g[v].size() < g[g[v].back()].size()) {
g[v].pop_back();
}
}
vector<int> used(n);
for (int u = 0; u < n; ++u) {
int cntl = 0;
for (auto v: g[u]) {
cntl++;
used[v] = true;
}
for (auto v: g[u]) {
int cntr = 0;
cntl--;
for (auto v2: g[v]){
if (used[v2]){
cntl--;
} else {
cntr++;
}
}
if (cntl && cntr){
for (auto v2: g[v]){
used[v2] ^= 1;
}
for (auto v2: g[u]){
if (used[v2]){
cout << v2 + 1 << " ";
break;
}
}
for (auto v2: g[v]){
used[v2] ^= 1;
}
cout << u + 1 << " " << v + 1 << " ";
for (auto v2: g[v]){
if (used[v2] == 0){
cout << v2 + 1 << "\n";
break;
}
}
return 0;
}
for (auto v2: g[v]){
if (used[v2]){
cntl++;
} else {
cntr--;
}
}
cntl++;
}
for (auto v: g[u]) {
cntl++;
used[v] = false;
}
}
cout << "no" << "\n";
}
// region POZOR
template<typename T>
ostream &operator<<(ostream &os, vector<T> &a) {
for (int i = 0; i < a.size(); i++)
os << a[i] << " \n"[i == a.size() - 1];
return os;
}
template<typename T>
istream &operator>>(istream &is, vector<T> &a) {
for (auto &i: a)
is >> i;
return is;
}
// endregion
