#include <stdio.h>
#include <vector>
#include <set>
#pragma warning(disable:4996) 

using namespace std;

vector<set<pair<int,int> > > g;     // target vertex, directed edge
vector<int> visedge;                // visit flag for each directed edge

bool dfs(int paredge, int curr)
{
    auto it=g[curr].begin();
    while(it!=g[curr].end()) {
        int next=it->first;
        int edge=it->second;
        if(edge/2==paredge/2) {
            ++it;
            continue;
        }
        if(visedge[edge]) {
            return true;
        }
        visedge[edge]=1;
        if (dfs(edge, next)) {
            return true;
        }
        it=g[curr].erase(it++);     // erase finished edge
    }
    return false;
}

void solve(int n, int m, const vector<int>& a, const vector<int>& b, const vector<int> c)
{
    g.resize(n);
    visedge.resize(m*2);
    int i;
    for(i=0; i<m; i++) {
        g[a[i]].insert(make_pair(b[i],i*2));         // i*2   means edge i (0-indexed) with normal direction
        if(c[i]==1) {
            g[b[i]].insert(make_pair(a[i],i*2+1));   // i*2+1 means edge i (0-indexed) with reversed direction
        }
    }
    for(i=0; i<n; i++) {
        bool ret=dfs(-100, i);
        if(ret){
            printf("Yes\n"); return;
        }
    }
    printf("No\n");
    return;
}

int main(int argc, char* argv[])
{
    int n,m;
    scanf("%d%d", &n, &m);
    vector<int> a(m),b(m),c(m);
    int i;
    for(i=0; i<m; i++) {
        scanf("%d%d%d", &a[i], &b[i], &c[i]); a[i]--; b[i]--;
    }
	solve(n, m, a, b, c);

	return 0;
}