SIMD easy

https://codeforces.com/gym/101485 G

#pragma GCC optimize("Ofast")
#pragma GCC target("avx2")

#include <bits/stdc++.h>

using namespace std;

const int maxn = 1 << 18;
alignas(32) int a[maxn];
alignas(32) int b[maxn];
alignas(32) int c[maxn];
alignas(32) int posb[maxn];
alignas(32) int posc[maxn];
alignas(32) int specialC[maxn];

int getCount(int at) {
  int pb = posb[at];
  int pc = posc[at];
  int result = 0;
  for (int i = 0; i < pb; i++)
    result += b[i] < at && specialC[i] < pc;
  return result;
}

int main(int argc, char *argv[]) {
  ios::sync_with_stdio(false);
  cin.tie(nullptr);

  int n;
  cin >> n;
  for (int i = 0; i < n; i++) cin >> a[i], a[i]--;
  for (int i = 0; i < n; i++) cin >> b[i], b[i]--;
  for (int i = 0; i < n; i++) cin >> c[i], c[i]--;
  for (int i = 0; i < n; i++) posb[b[i]] = i;
  for (int i = 0; i < n; i++) posc[c[i]] = i;
  for (int i = 0; i < n; i++) b[posb[a[i]]] = i;
  for (int i = 0; i < n; i++) c[posc[a[i]]] = i;
  for (int i = 0; i < n; i++) posb[b[i]] = i;
  for (int i = 0; i < n; i++) posc[c[i]] = i;
  for (int i = 0; i < n; i++) specialC[i] = posc[b[i]];
  long long answer = 0;
  for (int i = 0; i < n; i++) answer += getCount(i);
  cout << answer;
}