Submission #988798

#	Time	Username	Problem	Language	Result	Execution time	Memory
988798		LOLOLO	Diversity (CEOI21_diversity)	C++17	64 / 100	27 ms	7376 KiB

diversity

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
 
#define           f     first
#define           s     second
#define           pb    push_back
#define           ep    emplace
#define           eb    emplace_back
#define           lb    lower_bound
#define           ub    upper_bound
#define       all(x)    x.begin(), x.end()
#define      rall(x)    x.rbegin(), x.rend()
#define   uniquev(v)    sort(all(v)), (v).resize(unique(all(v)) - (v).begin())
#define     mem(f,x)    memset(f , x , sizeof(f))
#define        sz(x)    (int)(x).size()
#define  __lcm(a, b)    (1ll * ((a) / __gcd((a), (b))) * (b))
#define          mxx    *max_element
#define          mnn    *min_element
#define    cntbit(x)    __builtin_popcountll(x)
#define       len(x)    (int)(x.length())
 
const int N = 3e5 + 10;
int cnt[N];

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    int n, q;
    cin >> n >> q;

    assert(q == 1);
    for (int i = 1; i <= n; i++) {
        int x;
        cin >> x;
        cnt[x]++;
    }

    vector <ll> val;
    for (int i = 1; i < N; i++) {
        if (cnt[i])
            val.pb(cnt[i]);
    }

    int l, r;
    cin >> l >> r;

    sort(all(val), greater <ll> ());
    deque <ll> dq;
    int odd = 0;
    ll ans = 0;

    for (auto x : val) {
        if (odd == 0) {
            dq.pb(x);
        } else {
            dq.push_front(x);
        }

        odd = 1 - odd;
        ans += x * (x + 1) / 2;
    } 

    ll sum = 0, nor = 0;
    while (sz(dq)) {
        ll t = dq.front();
        dq.pop_front();
        sum += nor;
        ans += (t * sum);
        nor += t;
        sum += t;
    }

    cout << ans << '\n';
    return 0;
} 

// (n + ) * n 

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