#include<bits/stdc++.h>
using namespace std;

int num_nodes,num_edges;
bool graph[100][100];


void read(){
	cin>>num_nodes>>num_edges;
	int a,b;
	for(int i=0;i<num_edges;i++){
		cin>>a>>b;
		graph[a-1][b-1]=graph[b-1][a-1]=true;
	}
}


void solve(){
	for(int i=0;i<num_nodes;i++){
		for(int k=0;k<num_nodes;k++){
			for(int j=0;j<num_nodes;j++){
				if(graph[i][k] && graph[k][j] && graph[j][i])
					cout<<i+1<<" "<<k+1<<" "<<j+1<<endl;
			}
		}
	}
}



int main(){
	read();
	solve();
}