#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;



bool dfs(int node,char* c,vector<int>* gr)
{
    c[node] = 'o';
    bool f = false;
    for(int i : gr[node])
    {
        if(c[i] == 'o')
        {
            return true;
        }
        else if(c[i] == 0 && dfs(i,c,gr))
        {
            return true;
        }
    }
    c[node] = 'c';
    return false;
}

int main()
{
    std::ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    int t,n,m,from,to,w;
    cin >> t;
    for(int j = 0;j<t;j++)
    {
    vector<int> gr[210000];
    cin >> n >> m;
    for(int i = 0;i<m;i++)
    {
        cin >> from >> to >> w;
        gr[from].push_back(to);
    }
    char color[210000];
    bool c = false;
        for(int p = 0;p<=n;p++)
        {
            color[p] = 0;
        }
    for(int k = 1;k<=n;k++)
    {

        if(color[k] == 0 && dfs(k,color,gr))
        {
            c = true;
            break;
        }
    }
        if(c)
        {
            cout << "true ";
        }
        else
        {
            cout << "false ";
        }
    }
}