Submission #1123645

#	Time	Username	Problem	Language	Result	Execution time	Memory
1123645		mychecksedad	Diversity (CEOI21_diversity)	C++20	64 / 100	7093 ms	18728 KiB

diversity

/* Author : Mychecksdead  */
#include<bits/stdc++.h>
using namespace std;
#define ll long long int
#define MOD (1000000000+7)
#define MOD1 (998244353)
#define pb push_back
#define all(x) x.begin(), x.end()
#define en cout << '\n'
#define ff first
#define ss second
#define pii pair<int,int>
#define vi vector<int>
const int N = 1e6+100, M = 1e5+10, K = 52, MX = 30;


int n, q, a[N];
ll ans[N], cur;
vector<array<int, 4>> Q;
vector<ll> freq(N), co(N);
set<int> S;
void add(int i){
  co[freq[a[i]]]--;
  if(co[freq[a[i]]] == 0) S.erase(freq[a[i]]);
  freq[a[i]]++;
  co[freq[a[i]]]++;
  if(co[freq[a[i]]] == 1) S.insert(freq[a[i]]);
}

void rem(int i){
  co[freq[a[i]]]--;
  if(co[freq[a[i]]] == 0) S.erase(freq[a[i]]);
  freq[a[i]]--;
  co[freq[a[i]]]++;
  if(co[freq[a[i]]] == 1 && freq[a[i]] > 0) S.insert(freq[a[i]]);
}

ll get_sq(ll x){
  return (x+1)*(2*x+1)*x/6;
}

ll get_li(ll x){
  return (x*(x+1))>>1;
}

void solve(){
  cin >> n >> q;
  for(int i = 1; i <= n; ++i){
    cin >> a[i];
  }
  const int SS = sqrt(n);
  for(int i = 1; i <= q; ++i){
    int l, r; cin >> l >> r;
    Q.pb({l / SS, r, l, i});
  }

  sort(all(Q));

  cur = 0;
  int L = 1, R = 0;
  for(auto p: Q){
    while(R < p[1]){
      ++R;
      add(R);
    }
    while(L > p[2]){
      --L;
      add(L);
    }
    while(R > p[1]){
      rem(R);
      --R;
    }
    while(L < p[2]){
      rem(L);
      ++L;
    }

    cur = 0;

    ll odd = 0, even = 0, tot = 0, d = 0;

    for(ll pp: S){
      ll k = co[pp];
      ll x = (k + 1) >> 1;
      ll y = k >> 1;
      if((d & 1)) swap(x, y);
      // cout << x << ' ' << y << '\n';
      cur += x * odd * odd;
      cur += 2 * get_li(x - 1) * odd * pp;
      cur += get_sq(x - 1) * pp * pp;
      cur += y * even * even;
      cur += 2 * get_li(y - 1) * even * pp;
      cur += get_sq(y - 1) * pp * pp;

      odd += x * pp, even += y * pp;
      // else odd += y * pp, even += x * pp;

      tot += k * pp;
      d += k;
    } 

    // cout   << odd << ' ' << even << ' ' << cur << '\n';
    odd = 0, even = 0;
    ll dd = 0;
    for(ll pp: S){
      ll k = co[pp];
      ll x = (k + 1) >> 1;
      ll y = k >> 1;
      if((dd & 1)) swap(x, y);
      ll P = (tot - odd - pp);
      ll T = (tot - even - pp);
      cur += x * P * P;
      cur -= 2 * get_li(x - 1) * P * pp;
      cur += get_sq(x - 1) * pp * pp;
      cur += y * T * T;
      cur -= 2 * get_li(y - 1) * T * pp;
      cur += get_sq(y - 1) * pp * pp;

      odd += x * pp, even += y * pp;
      // else odd += y * pp, even += x * pp;
      dd += k;
    }
    // cout << d << ' ' << tot << ' ' << cur << ' ' ;
    ans[p[3]] = (d * tot * (tot+1) - tot * (d-1) - cur) >> 1;
  }


  for(int i = 1; i <= q; ++i){
    cout << ans[i] << '\n';
  }
}


int main(){
  cin.tie(0); ios::sync_with_stdio(0);
  int tt = 1, aa;
  // freopen("in.txt", "r", stdin);
  // freopen("out.txt", "w", stdout);
  while(tt--){
    solve();
    en;
  }
  cerr<<"time taken : "<<(float)clock()/CLOCKS_PER_SEC<<" seconds\n";
  return 0;
} 

• Subtask 1: 4 / 4
• Subtask 2: 10 / 10
• Subtask 3: 8 / 8
• Subtask 4: 16 / 16
• Subtask 5: 26 / 26
• Subtask 6: 0 / 36