我的这份代码在 usaco 上能够通过，而洛谷只有 6 分：

#include <bits/stdc++.h>

using namespace std;

const int kMaxN = 1e5 + 5;

class BIT {
  public:
    void upd(int x, int v) {
      for (; x <= n; x += x & -x) {
        c[x] += v;
      }
    }
    int qry(int x) {
      int ret = 0;
      for (; x; x -= x & -x) {
        ret += c[x];
      }
      return ret;
    }
    BIT() {}
    BIT(int _n) : n(_n) {}
  private:
    int n, c[kMaxN];
} b;

int n, k, idx, tot;
int a[kMaxN], c[kMaxN];

int main() {
  cin >> n;
  for (int i = 1; i <= n; ++i) {
    cin >> a[i];
  }
  b = BIT(n);
  a[n + 1] = n + 1;
  for (int i = n; i; --i) {
    if (a[i] < a[i + 1]) {
      b.upd(a[i], 1), ++tot;
    } else {
      idx = i; break ;
    }
  }
  for (int i = 1; i <= idx; ++i) {
    int x = b.qry(a[i]) + 1;
    ++tot;
    c[++k] = n - tot + x - 1;
    b.upd(a[i], 1);
  }
  cout << k << endl;
  for (int i = 1; i <= k; ++i) {
    cout << c[i];
    if (i != k) cout << ' ';
  }
  return 0;
}