#include <bits/stdc++.h>
#define SPED \
ios_base::sync_with_stdio(false); \
cin.tie(0); \
cout.tie(0);
#define endl "\n"
#define fi first
#define se second
#define lint long long
#define fami signed
#define lore main
#define freefire freopen
const lint INF = 0x1f1f1f1f1f1f1f1f;
const lint NEG = 0xE1E1E1E1E1E1E1E1;
using namespace std;
bool x[100005];
int n, q, bit[100005], idx[30], a[100005], pref[100005];
string s;
vector<int> Query[100005];
void upd(int idx, lint k)
{
for (; idx <= n; idx += idx & -idx)
bit[idx] += k;
}
lint get(int idx)
{
lint res = 0;
for (; idx; idx -= idx & -idx)
res += bit[idx];
return res;
}
lint query(int l, int r)
{
return get(r) - get(l - 1);
}
bool check(lint mid)
{
memset(bit, 0, sizeof bit);
memset(x, 0, sizeof x);
memset(pref, 0, sizeof pref);
memset(idx, 0, sizeof idx);
for (int i = 1; i <= mid; i++)
{
x[a[i]] = true;
pref[a[i]] = 1;
}
for (int i = 1; i <= n; i++)
pref[i] += pref[i - 1];
for (int i = 1; i <= n; i++)
{
if (!x[i])
{
if (idx[s[i] - 'a'])
upd(idx[s[i] - 'a'], -1);
idx[s[i] - 'a'] = i;
upd(i, 1);
}
for (auto l : Query[i])
{
if (query(l, i) == i - l + 1 - (pref[i] - pref[l - 1]))
continue;
else
return false;
}
}
return true;
}
lint binaryu()
{
lint l = 0, r = n, mid, ans = -1;
while (l <= r)
{
mid = l + r >> 1;
if (check(mid))
{
ans = mid;
r = mid - 1;
}
else
l = mid + 1;
}
return ans;
}
fami lore()
{
SPED;
cin >> s >> q;
n = s.size();
s = " " + s;
for (int i = 1; i <= q; i++)
{
int l, r;
cin >> l >> r;
Query[r].emplace_back(l);
}
for (int i = 1; i <= n; i++)
cin >> a[i];
cout << binaryu();
}
// Let your soul wander where dreams are born.
