#include<bits/stdc++.h>
using namespace std ;
typedef long long ll ;
typedef unsigned long long ull ;
typedef pair < int , int > pii ;
#define fi first
#define se second
mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());

const int MAXN = 5e5 + 7 ;

int n , m ;
pii a[ MAXN ] ;

vector < int > v[ MAXN ] ;
int wh[ MAXN ] ;
int ans[ MAXN ] ;

void solve ( ) {
    cin >> n >> m ;
    int mx = 0 ;
    for ( int i = 1 ; i <= 2 * m ; ++ i ) {
        cin >> a[ i ].fi >> a[ i ].se ;
        if ( a[ i ].fi != a[ i ].se ) { ++ mx ; }
    }
    if ( mx < m ) {
        cout << "-1\n" ;
        return ;
    }
    for ( int i = 1 ; i <= n ; ++ i ) {
        v[ i ].clear ( ) ;
        wh[ i ] = 0 ;
        ans[ i ] = 0 ;
    }
    for ( int i = 1 ; i <= 2 * m ; ++ i ) {
        if ( a[ i ].fi == a[ i ].se ) { continue ; }
        v[ a[ i ].se ].push_back ( a[ i ].fi ) ;
    }
    for ( int i = 1 ; i <= n ; ++ i ) {
        sort ( v[ i ].begin ( ) , v[ i ].end ( ) ) ;
    }
    int k = m ;
    for ( int i = n ; i >= 1 ; -- i ) {
        int sz = v[ i ].size ( ) ;
        if ( sz == 0 ) { continue ; }
        if ( k >= sz ) {
            k -= sz ;
            wh[ i ] = v[ i ].back ( ) ;
        }
        else {
            if ( k > 0 ) {
                wh[ i ] = v[ i ][ k ] ;
                k = 0 ;
            }
        }
    }
    for ( int i = 1 ; i <= n ; ++ i ) {
        if ( wh[ i ] == 0 ) { ans[ i ] = i ; }
        else { ans[ i ] = ans[ wh[ i ] ] ; }
    }
    for ( int i = 1 ; i <= n ; ++ i ) {
        cout << ans[ i ] << " " ;
    }
    cout << "\n" ;
}

int main ( ) {
    ios_base :: sync_with_stdio ( false ) ;
    cin.tie ( NULL ) ;
    int t = 1 ; cin >> t ; 
    while ( t -- ) { solve ( ) ; }
    return 0 ;
}