#include "testlib.h"

using namespace std;
using ll = long long;

const int MX = 1e9;

int main(int argc, char *argv[]) {
    registerValidation(argc, argv);

    ll n = inf.readLong(1LL, MX, "N");
    inf.readSpace();
    ll m = inf.readLong(0, n * (n - 1), "M");
    inf.readEoln();

    set<pair<int, int> > edges;
    for (ll i = 1; i <= m; i++) {
        ll s, e;
        double len;
        s = inf.readLong(1LL, n);
        inf.readSpace();
        e = inf.readLong(1LL, n);
        inf.readSpace();
        len = inf.readDouble();
        inf.readEoln();

        ensuref(s != e, "s must not be equal to e: edge: %lld -> %lld", s, e);
        ensuref(len >= 0,
                "len must be greater than or equal to zero: %lld->%lld, %lf", s,
                e, len);

        ensuref(!edges.contains({s, e}),
                "Edges must be unique: multiple edge %lld -> %lld", s, e);

        edges.emplace(s, e);
    }
    inf.readEof();
}