#include <iostream>
#include <vector>

using namespace std;
  
 
void addEdge(vector<int> adj[], int x, int y) 
{ 
    if (x != y)
    {
        adj[x].push_back(y); 
    }   
    adj[y].push_back(x); 
} 
  
void printGraph(vector<int> adj[], int V) 
{ 
    cout << "lista: \n";
    for (int v = 0; v < V; ++v) 
    { 
        cout << v+1 << ":"; 
        for (auto x : adj[v]) 
           cout << " " << x+1; 
        printf("\n"); 
    } 
} 
  

int main() 
{ 
    int n, m; cin >> n >> m;
    vector<int> adj[n]; 
    int tablicaaa[n][n] = {0};
    int x, y;
    for (int i = 0; i < m; i++)
    {
        cin >> x >> y;
        addEdge(adj, x-1, y-1);
        tablicaaa[x-1][y-1] = 1;
        tablicaaa[y-1][x-1] = 1;
    }
    printGraph(adj, n); 
    return 0; 
} 

// 5 7 0 1 0 4 1 2 1 3 1 4 2 3 3 4
//7 12 1 2 1 4 2 3 3 4 3 2 4 5 4 6 4 7 7 7 5 6 5 7 6 7