Submission #519273

#	Time	Username	Problem	Language	Result	Execution time	Memory
519273		Keshi	Diversity (CEOI21_diversity)	C++17	64 / 100	7097 ms	6580 KiB

diversity

//In the name of God
#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef pair<ll, ll> pll;

const ll maxn = 3e5 + 100;
const ll mod = 1e9 + 7;
const ll inf = 1e18;

#define fast_io ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define file_io freopen("input.txt", "r+", stdin);freopen("output.txt", "w+", stdout);
#define pb push_back
#define Mp make_pair
#define F first
#define S second
#define Sz(x) ll((x).size())
#define all(x) (x).begin(), (x).end()

ll pw(ll a, ll b){
	ll c = 1;
	while(b){
		if(b & 1) c = c * a % mod;
		a = a * a % mod;
		b >>= 1;
	}
	return c;
}

int n, q, a[maxn], c[maxn], b[maxn];

int main(){
	fast_io;

	cin >> n >> q;
	for(int i = 0; i < n; i++){
		cin >> a[i];
	}
	while(q--){
		int l, r;
		cin >> l >> r;
		l--;
		for(int i = l; i < r; i++){
			c[a[i]]++;
		}
		vector<int> vec;
		for(int i = l; i < r; i++){
			if(c[a[i]]){
				vec.pb(c[a[i]]);
				c[a[i]] = 0;
			}
		}
		sort(all(vec));
		l = 0, r = Sz(vec) - 1;
		ll s = 0;
		for(int i = 0; i < Sz(vec); i++){
			s += vec[i];
			if(i & 1){
				b[r--] = vec[i];
			}
			else{
				b[l++] = vec[i];
			}
		}
		ll x = 0, ans = 0;
		ll m = s;
		for(int i = 0; i < Sz(vec); i++){
			s -= b[i];
			ans += m * (m + 1) / 2 - x * (x + 1) / 2 - s * (s + 1) / 2;
			x += b[i];
		}
		cout << ans << "\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