Submission #866217

#	Time	Username	Problem	Language	Result	Execution time	Memory
866217		TAhmed33	Izbori (COCI22_izbori)	C++98	40 / 110	3076 ms	10376 KiB

Main

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
inline ll trig (ll x) {
	return x * (x + 1) / 2;
}
ll get2 (ll a, ll b, ll c) {
	a = min(a, c); b = min(b, c);
	c = min(c, a + b);
	return (c - b) * (b + 1) + (c + 1) * (a - c + b + 1) - trig(a) + trig(c - b - 1);
}
const int MAXN = 2e5 + 25;
int arr[MAXN], n;
vector <int> occ[MAXN];
vector <int> d;
//2 * x - 2 - r + l >= k1 + k2 >= 0
//0 <= k1 < a
//0 <= k2 < b
struct bit { 
	int tree[2 * MAXN + 25] = {};
	void add (int pos, int val) {
		for  (; pos < 2 * MAXN + 25; pos += pos & (-pos)) tree[pos] += val;
	}
	ll get (int pos) {
		ll sum = 0; for (; pos; pos -= pos & (-pos)) sum += tree[pos];
		return sum;
	}
};
bit cur;
int a[MAXN];
ll solve1 (int x) {
	memset(cur.tree, 0, sizeof(cur.tree));
	for (int i = 1; i <= n; i++) {
		a[i] = -1;
	}
	for (auto i : occ[x]) a[i] = 1;
	cur.add(MAXN, 1); 
	ll ret = 0;
	for (int i = 1; i <= n; i++) {
		a[i] += a[i - 1];
		ret += cur.get(a[i] - 1 + MAXN);
		cur.add(a[i] + MAXN, 1);
	}
	return ret;
}
ll solve2 (int x) {
	ll ret = (int)occ[x].size() - 2;
	for (int i = 1; i < (int)occ[x].size() - 2; i--) {
		for (int j = i + 1; j < (int)occ[x].size() - 1; j++) {
			ret += get2(occ[x][i] - occ[x][i - 1], occ[x][j + 1] - occ[x][j], 2 * (j - i + 1) - 2 - occ[x][j] + occ[x][i]);
		}
	}
	return ret;
}
int main () {
	cin >> n;
	for (int i = 1; i <= n; i++) {
		cin >> arr[i];
		d.push_back(arr[i]);
	}
	sort(d.begin(), d.end()); d.resize(unique(d.begin(), d.end()) - d.begin());
	for (int i = 1; i <= n; i++) arr[i] = lower_bound(d.begin(), d.end(), arr[i]) - d.begin();
	for (int i = 1; i <= n; i++) {
		occ[arr[i]].push_back(i);
	}
	ll sum = 0;
	int x = sqrt(n); while (x * x < n) x++; while (x * x > n) x--;
	for (int i = 0; i < n; i++) {
		if (occ[i].empty()) continue;
		if ((int)occ[i].size() > x) sum += solve1(i);
		else {
			occ[i].push_back(n + 1);
			occ[i].insert(occ[i].begin(), 0);
			sum += solve2(i);
		}
	}
	cout << sum << '\n';
}

• Subtask 1: 10 / 10
• Subtask 2: 15 / 15
• Subtask 3: 15 / 15
• Subtask 4: 0 / 70