#include<iostream>
#include<cstdio>
#include<cstring>
#define ull unsigned long long
using namespace std;
int n, m;
bool book_ani[10000003];
ull k;
int ani[10000003], ans;
unsigned long long c;
struct Edge
{
	int to, next;
}edge[10000003];
int head[100], cnt;
void add(int a, int b)//无边权
{
	edge[++cnt].to = b;
	edge[cnt].next = head[a];
	head[a] = cnt;
}
void init()
{
	int t;
	scanf("%d%d%d", &n, &m, &t);
	cin>>k;
	for (int i = 1; i <= n; ++i)
	{
		scanf("%d", &t);
		ani[i] = t;
		book_ani[t] = true;
	}
	for (int i = 1, p, q; i <= m; ++i)
	{
		scanf("%d%d", &p, &q);
		add(p, q);
	}
}
void solve()
{
	for (int i = 1; i <= n; ++i)//make list
	{
		long long index = 0, temp = ani[i];
		while (temp > 0)
		{
			if ((temp & 1) == 1)//需要加饲料
				for (int j = head[index]; j; j = edge[j].next)
					if( ( ( c>>(edge[j].to-1) )&1 ) !=1 )
						c += (1 << (edge[j].to - 1));
			temp >>= 1;
			++index;
		}
	}
	for (int i = 0; i < (1 << k); ++i)
	{
		long long index = 0, flag = 0, temp = i;
		if (book_ani[i])
			continue;
		while (temp > 0)
		{
			if ((temp % 2) == 1)//需要加饲料
				for (int j = head[index]; j; j = edge[j].next)
				{
					if (((c >> (edge[j].to - 1)) & 1) == 1);
					else
					{
						flag = 1;
						break;
					}
				}
			if (flag)
				break;
			temp >>= 1;
			++index;
		}
		if (!flag)
			++ans;
		flag = 0;
		index = 0;
	}
}
int main()
{
	//freopen("zoo.in","r",stdin);
	//freopen("zoo.out","w",stdout);
	init();
	solve();
	printf("%d", ans);
}