// what is matter? never mind. 
//#pragma GCC optimize("Ofast")
//#pragma GCC optimize("unroll-loops")
//#pragma GCC target("sse,sse2,sse3,sse4,popcnt,abm,mmx,avx,avx2") 
#include<bits/stdc++.h>
#define For(i,a,b) for(int i=(a);i<=(b);++i)
#define Rep(i,a,b) for(int i=(a);i>=(b);--i)
#define ll long long
//#define int long long
#define ull unsigned long long
#define SZ(x) ((int)((x).size()))
#define ALL(x) (x).begin(),(x).end()
using namespace std;
inline int read()
{
    char c=getchar();int x=0;bool f=0;
    for(;!isdigit(c);c=getchar())f^=!(c^45);
    for(;isdigit(c);c=getchar())x=(x<<1)+(x<<3)+(c^48);
    if(f)x=-x;return x;
}

#define fi first
#define se second
#define pb push_back
#define mkp make_pair
typedef pair<int,int>pii;
typedef vector<int>vi;

#define maxn 2000005
#define inf 0x3f3f3f3f

int n,m,deg[maxn];
set<int> e[maxn];
bool vis[maxn];

signed main()
{
	cin>>n>>m;
	For(i,1,m){
		int u,v;cin>>u>>v;
		e[u].insert(v),e[v].insert(u);
	}
	For(u,1,n){
		for(int v1:e[u]) for(int v2:e[u]) for(int v3:e[u]) 
			if(v1!=v2&&v2!=v3&&e[v1].count(v2)&&e[v2].count(v3)&&e[v1].count(v3)){
				cout<<"ok"<<endl;
				exit(0);
			}
	}
	cout<<"mark"<<endl;
	vi o;
	For(i,1,n) if(e[i].size()) {
		int j=*e[i].begin();
		o.pb(i),o.pb(j); vis[i]=vis[j]=1;
		int c=2;
		For(v,1,n) if(!vis[v] && c) --c,vis[v]=1,o.pb(v);
		break;
	}
	vector<pii>res;
	For(i,1,4)For(j,i+1,4)if(!e[o[i]].count(o[j]))res.pb(mkp(o[i],o[j]));
	cout<<SZ(res)<<endl;
	for(auto [x,y]:res)cout<<x<<" "<<y<<endl;
	return 0;
}
/*

*/