#include<bits/stdc++.h>
using namespace std;
#define fi first
#define sc second
#define pii pair<int,int>
#define pb push_back
const int maxn=1000+10;
int n,m,f[maxn][maxn],d[maxn];
void solve(){
    cin>>n>>m;
    for(int i=1,u,v;i<=m;i++) cin>>u>>v,f[u][v]=f[v][u]=1,d[u]++,d[v]++;
    int minn=1e9,mini=0;
    for(int i=1;i<=n;i++){
        if(d[i]<mini) mini=d[i],mini=i;
    } 
    int cnt=0;
    for(int i=1;i<=n;i++) cnt+=(d[i]==minn);
    if(minn==0&&cnt>=2) return cout<<"ok"<<endl,void();
    cout<<"mark"<<endl;
    cout<<5<<endl;
    for(int i=1;i<=n;i++){
        if(d[i]==2){
            for(int j=1;j<=n;j++){
                if(f[i][j]) cout<<i<<" "<<j<<endl;
            }
            break;
        }
    }
    for(int i=1;i<=n;i++){
        if(d[i]==3){
            for(int j=1;j<=n;j++){
                if(f[i][j]) cout<<i<<" "<<j<<endl;
            }
            break;
        }
    }
}
int main(){
    ios::sync_with_stdio(false);
    cin.tie(0),cout.tie(0);
    int t=1;
    // cin>>t;
    while(t--) solve();
    return 0;
}
/*
Samples
input:

output:

THINGS TODO:
检查freopen，尤其是后缀名
检查空间
检查调试语句是否全部注释
*/