#include <stdio.h>
#include <stdlib.h>
#include <math.h>

#define TRUE 1
#define FALSE 0
#define NEDEFINISANO -1
#define INF -1

typedef struct {
	int u;
	int v;
	int w;
} Veza;

Veza *veza;

int manji( int x, int y ) 
{
	if ( x == INF ) return FALSE;
	if ( y == INF )	return TRUE;
	
	return x < y;
}

int dajNajboljeg( int *obidjen, int *key, int n ) 
{
	int minCvor = NEDEFINISANO;
	int minKey = INF;
	
	for ( int i = 1; i <= n; i++ )
		if ( !obidjen[ i ] && manji( key[ i ], minKey ) )
			{
				minKey = key[ i ];
				minCvor = i;
			}
	
	return minCvor;
}

int main() 
{
	int n, m;	
	scanf("%d%d", &n, &m );
	
	int **graf = ( int ** ) malloc( ( n + 1 ) * sizeof( int * ) );
	int *prethodnik = ( int * ) malloc( ( n + 1 ) * sizeof( int ) );
	int *obidjen = ( int * ) malloc( ( n + 1 ) * sizeof( int ) );
	int *key = ( int * ) malloc( ( n + 1 ) * sizeof( int ) );
	Veza *veza = ( Veza * ) malloc( ( m + 1 ) * sizeof( Veza ) );
	
	for ( int i = 1; i <= n; i++ ) 
	{
		graf[ i ] = ( int * ) malloc( ( n + 1 ) * sizeof( int ) );
		prethodnik[ i ] = NEDEFINISANO;
		obidjen[ i ] = FALSE;
		key[ i ] = INF;
	}
	
	for ( int i = 1; i <= n; i++ )
		for ( int j = 1; j <= n; j ++ )
			graf[ i ][ j ] = INF;
			
	for ( int i = 1; i <= m; i++ ) 
		scanf("%d%d%d", &veza[ i ].u, &veza[ i ].v, &veza[ i ].w );
	
	int p, q;
	scanf("%d%d", &p, &q );
	
	for ( int i = 1; i <= m; i ++ )
	{
		if ( veza[ i ].w % p == 0 ) veza[ i ].w = ( veza[ i ].w / p - 1 ) * q;
		else veza[ i ].w = veza[ i ].w / p * q;
		
		graf[ veza[ i ].u ][ veza[ i ].v ] = graf[ veza[ i ].v ][ veza[ i ].u ] = veza[ i ].w;
	}
	
	int start = 1;
	int suma = 0;		
	key[ start ] = 0;	
	
	int u;
	while ( ( u = dajNajboljeg( obidjen, key, n ) ) != NEDEFINISANO )
	{
		obidjen[ u ] = TRUE;
		suma += key[ u ];
		
		// dodata veza ( prethodnik[ u ], u )
		
		for ( int v = 1; v <= n; v ++ )
			if ( graf[ u ][ v ] != INF && !obidjen[ v ] && manji( graf[ u ][ v ], key[ v ] ) )
			{
				key[ v ] = graf[ u ][ v ];
				prethodnik[ v ] = u;
			}
	}

	printf("%d\n", suma );
		
	return 0;
}