/*
入力 validation。WA になれば OK。
*/

#include "testlib.h"
#include<iostream>
using namespace std;

const int MIN_T = 0;
const int MAX_T = 1;
const int MIN_N = 1;
const int MAX_N = 2000;
const int MIN_M = 0;
const int MAX_M = 2000;
const int MIN_W = 1;
const int MAX_W = 1000000000;

int U[3000];
int V[3000];
int W[3000];

int main(){
	registerValidation();
	int T = inf.readInt(MIN_T, MAX_T, "T");
	inf.readEoln();
	int N = inf.readInt(MIN_N, MAX_N, "N");
	inf.readSpace();
	int M = inf.readInt(MIN_M, MAX_M, "M");
	inf.ensuref(M <= N * (N-1) / 2, "M is too large");
	inf.readEoln();
	for(int i=0;i<M;i++){
	    U[i] = inf.readInt(1, N, "u");
	    inf.readSpace();
	    V[i] = inf.readInt(1, N, "v");
	    inf.readSpace();
	    W[i] = inf.readInt(1, MAX_W, "w");
	    inf.readEoln();
	}
	inf.readEof();
	
	for(int i=0;i<M;i++){
	    inf.ensuref(U[i] != V[i], "u == v");
	}
	for(int i=0;i<M;i++){
	    for(int j=0;j<i;j++){
	        inf.ensuref(U[i]!=U[j]||V[i]!=V[j], "(ui,vi) == (uj,vj)");
	        inf.ensuref(U[i]!=V[j]||V[i]!=U[j], "(ui,vi) == (vj,uj)");
	    }
	}
	return 0;
}