#include <bits/stdc++.h>
using namespace std;
template <typename A, typename B>
string to_string(pair<A, B> p);
template <typename A, typename B, typename C>
string to_string(tuple<A, B, C> p);
template <typename A, typename B, typename C, typename D>
string to_string(tuple<A, B, C, D> p);
string to_string(const string& s) { return '"' + s + '"'; }
string to_string(const char& ch) {
  string s = "";
  s += ch;
  return "'" + s + "', ";
}
string to_string(const char* s) { return to_string((string)s); }
string to_string(bool b) { return (b ? "true" : "false"); }
string to_string(vector<bool> v) {
  bool first = true;
  string res = "{";
  for (int i = 0; i < static_cast<int>(v.size()); i++) {
    if (!first) {
      res += ", ";
    }
    first = false;
    res += to_string(v[i]);
  }
  res += "}";
  return res;
}
template <size_t N>
string to_string(bitset<N> v) {
  string res = "";
  for (size_t i = 0; i < N; i++) {
    res += static_cast<char>('0' + v[i]);
  }
  return res;
}
template <typename A>
string to_string(A v) {
  bool first = true;
  string res = "{";
  for (const auto& x : v) {
    if (!first) {
      res += ", ";
    }
    first = false;
    res += to_string(x);
  }
  res += "}";
  return res;
}
template <typename A, typename B>
string to_string(pair<A, B> p) {
  return "(" + to_string(p.first) + ", " + to_string(p.second) + ")";
}
template <typename A, typename B, typename C>
string to_string(tuple<A, B, C> p) {
  return "(" + to_string(get<0>(p)) + ", " + to_string(get<1>(p)) + ", " +
         to_string(get<2>(p)) + ")";
}
template <typename A, typename B, typename C, typename D>
string to_string(tuple<A, B, C, D> p) {
  return "(" + to_string(get<0>(p)) + ", " + to_string(get<1>(p)) + ", " +
         to_string(get<2>(p)) + ", " + to_string(get<3>(p)) + ")";
}
void debug_out() { cout << endl; }
template <typename Head, typename... Tail>
void debug_out(Head H, Tail... T) {
  cout << " " << to_string(H);
  debug_out(T...);
}
const long long mod = (long long)1000000007;
const long long inf = (long long)2e18;
long long n, m;
const long long maxn = 2e5 + 10;
long long a[maxn];
long long need[maxn];
long long ans = inf;
long long tot = 0;
long long cnt = 0;
bool check(long long mid) {
  vector<long long> have(m + 1, 0);
  bool ok = false;
  long long done = 0;
  42;
  for (long long i = 1; i <= mid; ++i) {
    ++have[a[i]];
    if (have[a[i]] == need[a[i]]) ++done;
  }
  42;
  ok |= (done == cnt);
  for (long long i = mid + 1; i <= n; ++i) {
    long long prev = i - mid;
    if (have[a[prev]] == need[a[prev]]) --done;
    --have[a[prev]];
    if (have[a[i]] + 1 == need[a[i]]) ++done;
    ++have[a[i]];
    ok |= (done == cnt);
    42;
  }
  42;
  42;
  if (ok) ans = min(ans, mid - tot);
  return ok;
}
void binsearch(long long lo, long long hi) {
  while (lo <= hi) {
    long long mid = (lo + hi) / 2;
    if (check(mid))
      hi = mid - 1;
    else
      lo = mid + 1;
  }
}
int32_t main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout << fixed << setprecision(9);
  cin >> n >> m;
  for (long long i = 1; i <= n; ++i) cin >> a[i];
  for (long long i = 1; i <= m; ++i) {
    cin >> need[i];
    tot += need[i];
    cnt += (need[i] > 0);
  }
  42;
  binsearch(1, n);
  if (ans == inf) ans = -1;
  cout << ans << '\n';
  return 0;
}
