Submission #993708

#	Time	Username	Problem	Language	Result	Execution time	Memory
993708		vladilius	Diversity (CEOI21_diversity)	C++17	64 / 100	66 ms	5584 KiB

diversity

#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using pii = pair<int, int>;
#define pb push_back
#define ff first
#define ss second
#define ins insert

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    
    int n, q; cin>>n>>q;
    vector<int> a(n + 1);
    for (int i = 1; i <= n; i++){
        cin>>a[i];
    }
    sort(a.begin() + 1, a.end());
    vector<int> b;
    int i = 1;
    while (i <= n){
        int j = i;
        while (j <= n && a[i] == a[j]){
            j++;
        }
        b.pb(j - i);
        i = j;
    }
    sort(b.begin(), b.end());
    n = (int) b.size();
    vector<int> x(n + 1);
    for (int i = 0; i < n; i++){
        if (i % 2){
            x[n - i / 2] = b[i];
        }
        else {
            x[i / 2 + 1] = b[i];
        }
    }

    ll out = 0, pr = 0;
    for (int i = 1; i <= n; i++) out += 1LL * x[i] * (x[i] + 1) / 2;
    int sum = 0;
    for (int i = 1; i <= n; i++){
        out += 1LL * x[i] * (1LL * i * sum - pr);
        sum += x[i];
        pr += 1LL * (i - 1) * x[i];
    }
    cout<<out<<"\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