#include<iostream>
#include<cstdio>
#include<algorithm>
#include<cassert>
#include<cmath>
#include<vector>
#include<map>
#include<set>
#include<string>
#include<queue>
#include<stack>
using namespace std;
#define MOD 1000000007
#define MOD2 998244353
#define INF ((1<<30)-1)
#define LINF (1LL<<60)
#define EPS (1e-10)
typedef long long Int;
typedef pair<Int, Int> P;


int n, m;
vector<int> edge[110000];
vector<int> rev[110000];
vector<int> group[110000];
int a, b, c;
bool done[110000];
Int comp[110000];
vector<int> nodes;

void dfs(int x, int last = -1){
    if(done[x])return;
    done[x] = true;
    for(auto to:edge[x]){
        if(to == last)continue;
        dfs(to, x);
    }
    nodes.push_back(x);
}

void dfs2(int x, int g, int last = -1){
    if(done[x])return;
    done[x] = true;
    group[g].push_back(x);
    comp[x] = g;
    for(auto to:rev[x]){
        if(to == last)continue;
        dfs2(to, g, x);        
    }
}

void scc(){
    for(int i = 1;i <= n;i++){
        dfs(i);
    }
    reverse(nodes.begin(), nodes.end());
    for(auto node:nodes){
        if(!done[node])
            dfs2(node, node);
    }
}

void ok(){
    cout << "Yes" << endl;
    exit(0);
}

void ng(){
    cout <<  "No" << endl;
    exit(0);
}

bool check(int g){
    int V = group[g].size();
    if(V == 0)return false;
    int E = 0;
    cout << "Group " << g << endl;
    for(auto v:group[g]){
        cout << v << " ";
        for(auto to:edge[v]){
            if(comp[to] == g)E++;
        }
    }cout << endl;
    if(E == V+1)return false;
    return true;
}

int main(){
    cin >> n >> m;
    for(int i = 0;i < m;i++){
        cin >> a >> b >> c;
        edge[a].push_back(b);
        rev[b].push_back(a);
        if(c==2){
            edge[b].push_back(a);
            rev[a].push_back(b);
        }
    }

    scc();

    for(int i = 1;i <= n;i++){
        if(check(i))ok();
    }
    ng();
    return 0;
}