#pragma GCC optimize("O1,O2,O3,Ofast,unroll-loops")
#include <bits/stdc++.h>
#include <string>
#include <iostream>
#include <cmath>
#include <numeric>
#include <stack>
#include <queue>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<int, int> pi;
typedef pair<ll, ll> pl;
typedef pair<ld, ld> pd;
typedef vector<int> vi;
typedef vector<bool> vb;
typedef vector<vector<int>> vvi;
typedef vector<vector<pi>> vvpi;
typedef vector<ld> vd;
typedef vector<long long> vl;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
#define FOR(i, a, b) for (ll i = a; i < (b); i++)
#define F0R(i, a) for (int i = 0; i < (a); i++)
#define FORd(i, a, b) for (int i = (b)-1; i >= a; i--)
#define F0Rd(i, a) for (int i = (a)-1; i >= 0; i--)
#define trav(a, x) for (auto &a : x)
#define uid(a, b) uniform_int_distribution<int>(a, b)(rng)
#define len(x) (int)(x).size()
#define mp make_pair
#define pb push_back
#define F first
#define nl endl
#define S second
#define lb lower_bound
#define ub upper_bound
#define aint(x) x.begin(), x.end()
#define raint(x) x.rbegin(), x.rend()
#define ins insert
const int M = 1e9+7;
void init(string name)
{
freopen((name + ".in").c_str(), "r", stdin);
freopen((name + ".out").c_str(), "w", stdout);
}
void fastIO()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
}
void solve()
{
string a;cin >> a;
int n = a.size();
int q;cin >> q;
vpi qu(q,{0,0});
FOR(i,0,q)cin >> qu[i].F >> qu[i].S;
vi ar(n);
FOR(i,0,n)cin >> ar[i];
int l = 0, r = n,ans = 0;
while(l<=r){
int mid = (l+r)/2;
vi can(n,1);
FOR(i,0,mid){can[ar[i]-1] = 0;}
vvi dp(n+1,vi(26,0));
FOR(i,0,n){
FOR(j,0,26){
if(a[i]-'a' == j && can[i])dp[i+1][j] = dp[i][j] + 1;
else dp[i+1][j] = dp[i][j];
}
}
int ok = 1;
FOR(i,0,q){
if(ok == 0)break;
FOR(j,0,26){
if(ok == 0)break;
if(dp[qu[i].S][j] - dp[qu[i].F-1][j] > 1)ok = 0;
}
}
// cerr << l << " " << mid << " " << r << endl;
// for(int b:can)cerr << b << " ";
// cerr << endl;
// for(auto b:dp){
// for(int c:b)cerr << c << " ";
// cerr << endl;
// }cerr << " | " << ok << endl << endl;
if(ok == 0)l = mid+1;
else {r = mid-1;ans = mid;}
}
cout << ans << endl;
}
int main()
{
fastIO();
// init("test");
int t = 1;
// cin >> t;
while (t--)
solve();
return 0;
}
