#include <bits/stdc++.h>
using namespace std;
#define int long long
const int N = 2e5+1;

vector<vector<int>>g(N);
vector<int>vis(N);
vector<int>top;

void dfs(int v)
{
    vis[v] = 1;
    for(int u : g[v])
    {
        if(!vis[u]) dfs(u);
        else if(vis[u] == 1) {cout << "NEM"; exit(0);}
    }
    vis[v] = 2;
    top.push_back(v);
}

signed main() {
    ios::sync_with_stdio(false);cin.tie(nullptr);
	int n, m; cin >> n >> m;
    for(int i = 0; i < n; i++) g[i].push_back(i+n);
    while(m--)
    {
        int t, a, b; cin >> t >> a >> b; a--; b--;
        if(t == 2) g[a+n].push_back(b);
        else
        {
            g[a].push_back(b+n);
            g[b].push_back(a+n);
        }
    }
    for(int i = 0; i < 2*n; i++)
    {
        if(!vis[i]) dfs(i);
    }
    cout << "IGEN\n";
    reverse(top.begin(), top.end());
    vector<int>ans(2*n);
    for(int i = 0; i < 2*n; i++)
    {
        ans[top[i]] = i+1;
    }
    for(int i = 0; i < n; i++)
    {
        cout << ans[i] << " " << ans[i+n] << '\n';
    }
}