#include <bits/stdc++.h>
using namespace std;
const int N=2e5+10;
const int inf=0x3f3f3f3f;
int n,m,k,dis[N],p[N],pos[N];
vector<int>G[N];
queue<int>q;
struct node{int v,x,y;};
priority_queue<node>pq;
bool operator < (const node &a,const node &b){
	return a.v>b.v;
}
int main(){
	freopen("Commute.in","r",stdin);
	freopen("Commute.out","w",stdout);
	scanf("%d %d %d",&n,&m,&k);
	for(int i=1,u,v;i<=m;i++){
		scanf("%d %d",&u,&v);
		G[v].push_back(u);
	}
	memset(dis,0x3f,sizeof(dis));
	dis[n]=0,q.push(n);
	while(q.size()){
		int x=q.front();q.pop();
		for(auto y:G[x]){
			if(dis[y]!=inf)continue;
			dis[y]=dis[x]+1;
			q.push(y);
		}
	}
	for(int i=1;i<=n;i++){
		scanf("%d",p+i);
		pos[p[i]]=i;
	}
	for(int i=1;i<=n;i++){
		pq.push(node{pos[i]+dis[i],i,pos[i]});
	}
	while(k--){
		int x,y;scanf("%d %d",&x,&y);
		pos[p[x]]=pos[p[y]]=0;
		swap(p[x],p[y]);
		pos[p[x]]=x,pos[p[y]]=y;
		pq.push(node{pos[p[x]]+dis[p[x]],p[x],pos[p[x]]});
		pq.push(node{pos[p[y]]+dis[p[y]],p[y],pos[p[y]]});
		while(1){
			node t=pq.top();
			if(pos[t.x]!=t.y){
				pq.pop();
			}else{
				printf("%d\n",t.v-1);
				break;
			}
		}
	}
	return 0;
}