#include <bits/stdc++.h>
using namespace std;
long long sqr(long long x) { return x * x; }
int mysqrt(long long x) {
  int l = 0, r = 1e9 + 1;
  while (r - l > 1) {
    int m = (l + r) / 2;
    if (m * (long long)m <= x)
      l = m;
    else
      r = m;
  }
  return l;
}
mt19937 rnd(1227);
mt19937_64 rndll(12365);
long long AR = 19, BR = 13, CR = 23, XR = 228, YR = 322, MODR = 1e9 + 993;
long long myrand() {
  long long ZR = (XR * AR + YR * BR + CR) % MODR;
  XR = YR;
  YR = ZR;
  return ZR;
}
const int Mod = 1e9 + 7;
int bpow(int x, int y) {
  if (y == 0) return 1;
  if (y == 1) return x;
  int ret = bpow(x, y >> 1);
  ret = (ret * (long long)ret) % Mod;
  if (y & 1) ret = (ret * (long long)x) % Mod;
  return ret;
}
int bdiv(int x, int y) { return (x * (long long)bpow(y, Mod - 2)) % Mod; }
void setmin(int &x, int y) { x = min(x, y); }
void setmax(int &x, int y) { x = max(x, y); }
void setmin(long long &x, long long y) { x = min(x, y); }
void setmax(long long &x, long long y) { x = max(x, y); }
int gcd(int a, int b) { return a ? gcd(b % a, a) : b; }
const long long llinf = 2e18 + 100;
const double eps = 1e-9;
const int maxn = 2e5 + 100, maxw = 1e7 + 100, inf = 2e9 + 100, sq = 300,
          mod = 1e9 + 7, LG = 17;
int n, m;
int a[maxn];
int q[maxn];
int main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  cin >> n >> m;
  for (int i = 0; i < n; i++) cin >> a[i], a[i]--;
  int S = 0;
  for (int i = 0; i < m; i++) cin >> q[i], S += q[i], q[i] *= -1;
  int last = 0;
  int rem = 0;
  for (int i = 0; i < m; i++)
    if (q[i] != 0) rem++;
  int ans = inf;
  for (int i = 0; i < n; i++) {
    while (last < n && rem > 0) {
      q[a[last]]++;
      if (q[a[last]] == 0) rem--;
      last++;
    }
    if (rem > 0) break;
    ans = min(ans, last - i - S);
    q[a[i]]--;
    if (q[a[i]] == -1) rem++;
  }
  if (ans == inf) ans = -1;
  cout << ans;
}
