hihocoder1175

#include<cstdio>
#include<algorithm>
#include<cstring>
#include<queue>
#include<cmath>
#include<vector>
using namespace std;
int pre[100005];
int val[100005];
queue<int> q;
vector<int> to[100005];
int main()
{
int n,m,a,b,k;
scanf("%d %d %d",&n,&m,&k);
{
memset(pre,0,sizeof pre);
memset(val,0,sizeof val);
for (int i = 1; i <= n; i++)
to[i].clear();
for (int i = 1; i <= k; i++)
{
scanf("%d",&a);
val[a]++;
}
for (int i = 0; i < m; i++)
{
scanf("%d %d",&a,&b);
pre[b]++;
to[a].push_back(b);
}
for (int i = 1; i <= n; i++)
{
if(!pre[i])
{
q.push(i);
}
}
while(!q.empty())
{
int now = q.front();
q.pop();
for (int i = 0; i < to[now].size(); i++)
{
pre[to[now][i]]--;
val[to[now][i]] += val[now];
val[to[now][i]] %= 142857;
if(pre[to[now][i]] == 0)
{
q.push(to[now][i]);
}
}
}
int sum = 0;
for (int i = 1; i <= n; i++)
{
sum += val[i];
sum %= 142857;
}
printf("%d\n",sum%142857);
}
}