#include <bits/stdc++.h>
using namespace std;
#define all(x) x.begin(), x.end()
#define MASK(i) (1LL << (i))
void ckmax(int& f, int s)
{
f = (f > s ? f : s);
}
void ckmin(int& f, int s)
{
f = (f < s ? f : s);
}
const int mod1 = 1035972859;
const int mod2 = 1704760909;
const int base = 1e6 + 5;
const int N = 1e6 + 5;
int p1[N], p2[N], inv1[N], inv2[N];
int power(long long a, int b, int mod)
{
long long res = 1;
while (b)
{
if (b & 1) (res *= a) %= mod;
(a *= a) %= mod;
b >>= 1;
}
return res;
}
struct fenwick
{
int n;
vector<long long> bit;
fenwick() {}
fenwick(int n)
{
this->n = n + 5;
bit.resize(n + 5);
}
void add(int pos, long long val)
{
while (pos < n)
{
bit[pos] += val;
pos += pos & -pos;
}
}
long long get(int pos)
{
long long ans = 0;
while (pos)
{
ans += bit[pos];
pos -= pos & -pos;
}
return ans;
}
long long get(int l, int r)
{
return get(r) - get(l - 1);
}
};
int32_t main()
{
ios_base::sync_with_stdio(false);
cin.tie(0);
p1[0] = p2[0] = 1;
for (int i = 1; i < N; i++)
{
p1[i] = (1LL * p1[i - 1] * base) % mod1;
p2[i] = (1LL * p2[i - 1] * base) % mod2;
}
inv1[N - 1] = power(p1[N - 1], mod1 - 2, mod1);
inv2[N - 1] = power(p2[N - 1], mod2 - 2, mod2);
for (int i = N - 2; i >= 0; i--)
{
inv1[i] = (1LL * inv1[i + 1] * base) % mod1;
inv2[i] = (1LL * inv2[i + 1] * base) % mod2;
}
int k, n;
cin >> k >> n;
vector<int> zzz(k), a(k);
for (int &i : zzz) cin >> i, i--;
for (int i = 0; i < k; i++)
{
a[zzz[i]] = i + 1;
}
{
auto cc = a;
sort(all(cc));
cc.erase(unique(all(cc)), cc.end());
for (int &i : a) i = upper_bound(all(cc), i) - cc.begin();
}
pair<long long, long long> hashed;
{
int h1 = 0, h2 = 0;
for (int j = 0; j < k; j++)
{
int x = a[j];
h1 = (h1 + 1LL * x * p1[j]) % mod1;
h2 = (h2 + 1LL * x * p2[j]) % mod2;
//cout << h1 << ' ' << h2 << ' ' << h3 << '\n';
}
hashed = {h1, h2};
}
vector<int> v(n);
for (int &i : v) cin >> i;
auto cc = v;
sort(all(cc));
cc.erase(unique(all(cc)), cc.end());
for (int &i : v) i = upper_bound(all(cc), i) - cc.begin();
fenwick tree1(n), tree2(n);
fenwick tree(n);
vector<int> has(n + 5);
long long H1 = 0, H2 = 0;
vector<int> ans;
for (int i = 0; i < n; i++)
{
int p = tree.get(v[i] - 1);
if (!has[v[i]])
{
tree.add(v[i], 1);
(H1 += tree1.get(v[i] + 1, n)) %= mod1;
(H2 += tree2.get(v[i] + 1, n)) %= mod2;
}
(H1 += (p + 1LL) * p1[i]) %= mod1;
(H2 += (p + 1LL) * p2[i]) %= mod2;
has[v[i]]++;
//tree1.update(v[i] + 1, n, base);
//tree2.update(v[i] + 1, n, base);
tree1.add(v[i], p1[i]);
tree2.add(v[i], p2[i]);
//cout << H1 << ' ' << H2 << '\n';
//cout << H1 << ' ' << H2 << ' ' << H3 << '\n';
if (i >= k - 1)
{
if (make_pair((H1 * inv1[i - k + 1]) % mod1, (H2 * inv2[i - k + 1]) % mod2) == hashed)
{
ans.push_back(i - k + 2);
}
int j = i - k + 1;
p = tree.get(v[j] - 1);
H1 = ((H1 - (p + 1LL) * p1[j]) % mod1 + mod1) % mod1;
H2 = ((H2 - (p + 1LL) * p2[j]) % mod2 + mod2) % mod2;
//tree1.update(v[j] + 1, n, inv1[1]);
//tree2.update(v[j] + 1, n, inv2[1]);
has[v[j]]--;
tree1.add(v[j], -p1[j]);
tree2.add(v[j], -p2[j]);
if (!has[v[j]])
{
H1 = (H1 - tree1.get(v[j] + 1LL, n) % mod1 + mod1) % mod1;
H2 = (H2 - tree2.get(v[j] + 1LL, n) % mod2 + mod2) % mod2;
tree.add(v[j], -1);
}
//cout << "- ";
//cout << (H1 * inv1[i - k + 1]) % mod1 << ' ' << (H2 * inv2[i - k + 1]) % mod2 << '\n';
}
}
cout << ans.size() << '\n';
for (int i : ans) cout << i << ' ';
return 0;
}
