#include <stdio.h>
#include <ctype.h>

#define N 10005
#define M 100005
 
 int hrana[M][3];
 int deg[N];
 int color[N];
 int index[N+1];
 int vrchol[N+1];
 
 /* hrany susediace s danym vrcholom*/
 int hrany[M*2];
 int vahy[M*2];
 
int n, m, z, max;

int budovy[N];
int zakladne[N];
int sucty[N];
int pocet;
 
/* dfs */
void DFS(int v)
{
	int i;
	int akt_hrana = 0;
	int akt_vaha = 0;
	color[v] = 1;
	/*printf("**** ahoj vrchol: %d\n", v+1);*/
	for(i = index[v]; i < index[v+1]; i++)
	{
		akt_hrana = hrany[i];
		akt_vaha = vahy[i];
		/*
		printf("navsteva hrana %d-%d (dlzka: %d)\n", v+1, akt_hrana+1, akt_vaha);
		*/
		if(color[akt_hrana] == 0)
		{
			sucty[akt_hrana] = sucty[v]+ akt_vaha;
			
			/* znicime mesto */
			if(  sucty[akt_hrana] < max)
			{	
				if(budovy[akt_hrana] == 1)
					pocet = pocet -1;
					
				budovy[akt_hrana] = 0;
			}
		
				
			DFS(akt_hrana);
		}
			
	}

}




int main(void) 
{
 	int v1, v2, w;
 	int x, y;
 	int tmp;
 	int i, a, teror;
 	char c;
 	
 	scanf("%d %d %d %d", &n, &m, &z, &max);
 	while (n != 0) {
	 	pocet = n;
	 	
	 	
	 	for(i=0; i < n; i++)
	 	{
	 		deg[i] = 0;
	 		budovy[i] = 1;
			zakladne[i] = 0;
	 	}

		/* hrany */ 	
	 	for(i=0; i < m; i++)
	 	{
	 		scanf("%d %d %d", &v1, &v2, &w);
	 		hrana[i][0] =  v1-1;	
	 		hrana[i][1] =  v2-1;
	 		hrana[i][2] =  w;
	 		deg[v1-1]++;
	 		deg[v2-1]++;
	 	}
	 	

		tmp=0;
	 	/* indexy */
	 	for(i=0; i < n+1; i++)
	 	{
	 		index[i] = tmp;
	 		vrchol[i] = index[i];
	 		tmp = tmp + deg[i];
	 	}

		 	
		/* zapiseme si body */
	 	for(i=0; i < m; i++)
	 	{
	 		x = hrana[i][0];
	 		y = hrana[i][1];
	 		
	 		
	 		hrany[vrchol[y]] = x;
	 		hrany[vrchol[x]] = y;
	 		
	 		vahy[vrchol[y]++] = hrana[i][2];
	 		vahy[vrchol[x]++] = hrana[i][2];
	 	}
	 	hrany[2*m] = -1;
	 	
	 	/*
	 	for(i=0; i < n+1; i++)
	 		printf("index[%d] = %d\n", i, index[i]);
	 		
	 	for(i=0; i < 2*m+1; i++)
	 		printf("hrany[%d] = %d, vaha: %d\n", i, hrany[i], vahy[i]);
	 	*/
	 	
	 	for (a=0; a < z; a++)
	 	{
	 		scanf("%d", &teror);
	 	
		 	/* ideme na DFS */
		 	for(i=0; i < n; i++)
		 	{
		 		sucty[i] = 0;	
		 		color[i] = 0;
		 	}
		 	zakladne[teror-1] = 1;		
		 	sucty[teror-1] = 0;
		 	if(budovy[teror-1] == 1)
		 	{
		 		pocet--;
		 		budovy[teror-1] = 0;	
		 	}
		 	DFS(teror-1);
		 	
		 	
			/*
		 	for(i=0; i < n; i++)
		 		printf("budovy[%d] = %d\n", i+1, budovy[i]);
		 	
		 	for(i=0; i < n; i++)
		 		printf("sucty[%d] = %d\n", i+1, sucty[i]);
		 	*/
		 		
		 	printf("%d\n", pocet);
		 	
	 	}
	 	c = getchar();
		c = getchar();
		scanf("%d %d %d %d", &n, &m, &z, &max);
 		printf("\n");
 	}


 	
 	
 	return 0;
 }