Submission #1161690

#	Time	Username	Problem	Language	Result	Execution time	Memory
1161690		antonn	Diversity (CEOI21_diversity)	C++20	0 / 100	1 ms	528 KiB

diversity

#include <bits/stdc++.h>

#define F first
#define S second
 
using namespace std;
using ll = long long;
using pi = pair<int, int>;
using vi = vector<int>;
 
template<class T> bool ckmin(T& a, T b) { return b < a ? a = b, true : false; }
template<class T> bool ckmax(T& a, T b) { return a < b ? a = b, true : false; }

const int N = 3e5 + 7;

int a[N], cnt[N];

ll get(vector<int> v) {
    int n = v.size();
    ll ans = 0;
    for (int i = 0; i < n; ++i) {
        set<int> s;
        for (int j = i; j < n; ++j) {
            s.insert(v[j]);
            ans += s.size();
        }
    }
    return ans;
}

/**
10 1
1 3 3 2 1 3 3 1 1 3 
1 10

6 1
2 4 3 5 4 3 
1 6
**/

int main() {
    ios::sync_with_stdio(0); cin.tie(0);
    
    int n, q; cin >> n >> q;
    for (int i = 1; i <= n; ++i) cin >> a[i];
    
    for (int iq = 1; iq <= q; ++iq) {
        int l, r; cin >> l >> r;
        for (int j = l; j <= r; ++j) ++cnt[a[j]];
        
        vector<int> f;
        for (int j = 1; j < N; ++j) if (cnt[j] != 0) f.push_back(cnt[j]);
        sort(f.begin(), f.end());
        
        vector<int> v(f.size());
        int id = 0;
        for (int j = 0; j < f.size(); j += 2) v[id++] = f[j];
        id = f.size() - 1;
        for (int j = 1; j < f.size(); j += 2) v[id--] = f[j];
        
        ll len = r - l + 1;
        ll ans = len * (len + 1) / 2;
        ll s = 0;
        for (int j = v.size() - 1; j >= 0; --j) {
            s += v[j];
            if (j >= (v.size() + 1) / 2) ans += s * (len - s);
        }
        cout << ans << "\n";
    }
}

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