#include <bits/stdc++.h>
using namespace std;
typedef pair<int,int> ii;
int prevArr[100010];
struct node{
int s,e,m,v;
node *l,*r;
node(int _s,int _e){
s = _s;
e = _e;
m = (s+e)/2;
v = 0;
if (s != e){
l = new node(s,m);
r = new node(m+1,e);
}
}
void updateAll(){
if (s == e) v = prevArr[s];
else{
l->updateAll();
r->updateAll();
v = max(l->v,r->v);
}
}
int rmq(int x,int y){
if(s == x && e == y) return v;
if (y <= m) return l->rmq(x,y);
if (x > m) return r->rmq(x,y);
return max(l->rmq(x,m),r->rmq(m+1,y));
}
}*root;
int main(){
string s;
cin >> s;
int n,q;
cin >> q;
n = s.length();
root = new node(0,n-1);
ii arr[q];
for (int i = 0; i < q; i++) {
cin >> arr[i].first>> arr[i].second;
arr[i].first--;
arr[i].second--;
}
int toss[n+1];
for (int i = 1; i <= n; i++) {
cin >> toss[i];
toss[i]--;
}
int l = 0,r = n+1;
while (l != r){
int m = (l+r)/2;
//cout << m << "here\n";
char temp[n];
for (int i =0; i < n; i++) temp[i] = s[i];
for (int i = 1; i <= m; i++) temp[toss[i]] = '-';
int pos[26];
for (int i = 0; i < 26; i++) pos[i] = -1;
for (int i = 0; i < n; i++){
if (temp[i] == '-') prevArr[i] = -1;
else{
prevArr[i] = pos[temp[i]-97];
pos[temp[i]-97] = i;
}
//cout << prevArr[i] << " ";
}
//cout << "\n";
root->updateAll();
int can = 1;
for (int i = 0; i < q; i++){
//cout << arr[i].first << " " << arr[i].second << "\n";
//cout << root->rmq(arr[i].first,arr[i].second) << "hi\n";
if (root->rmq(arr[i].first,arr[i].second) >= arr[i].first) can = 0;
}
if (can) r = m;
else l = m+1;
}
cout << l;
}
