Submission #167953

#	Time	Username	Problem	Language	Result	Execution time	Memory
167953		Thuleanx	Untitled (POI11_rot)	C++14	100 / 100	171 ms	13236 KiB

Main

#include <bits/stdc++.h>
using namespace std;

const int N = 4e5+7;
int n, t;
int tree[N];
int l[N], r[N], lt[N], rt[N];
vector<int> p;
long long ans;

void add(int v, int x) {
	for (; v < N; v|=v+1)
		tree[v] += x;
}

int sum(int v) {
	int ans = 0;
	for (; v >= 0; v = (v&(v+1))-1)
		ans += tree[v];
	return ans;
}

int dfs() {
	int x; cin>>x;
	if (x) {
		l[t] = r[t] = p.size();
		p.push_back(x-1);
	} else {
		int left = dfs(), right = dfs();
		l[t] = min(l[left], l[right]);
		r[t] = max(r[left], r[right]);
		lt[t] = left; rt[t] = right;
	}
	return t++;
}

void dfsSolve(int v, bool store) {
	if (l[v] == r[v]) {
		if (store)
			add(p[l[v]], 1);
		return;
	}
	if (r[rt[v]]-l[rt[v]] > r[lt[v]]-l[lt[v]])
		swap(lt[v], rt[v]);
	dfsSolve(rt[v], 0);
	dfsSolve(lt[v], 1);
	long long res = 0;
	for (int x = l[rt[v]]; x <= r[rt[v]]; x++)
		res += sum(p[x]);
	ans += min(res, 1LL*(r[rt[v]]-l[rt[v]]+1)*(r[lt[v]]-l[lt[v]]+1)-res);
	
	if (store)
		for (int x = l[rt[v]]; x <= r[rt[v]]; x++)
			add(p[x], 1);
	else
		for (int x = l[lt[v]]; x <= r[lt[v]]; x++)
			add(p[x], -1);
}

int main() {
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);

	cin >> n;
	ans = t = 0;
	dfsSolve(dfs(), 0);
	cout << ans << endl;

	return 0;
}

• Subtask 1: 9 / 9
• Subtask 2: 9 / 9
• Subtask 3: 9 / 9
• Subtask 4: 9 / 9
• Subtask 5: 9 / 9
• Subtask 6: 9 / 9
• Subtask 7: 9 / 9
• Subtask 8: 9 / 9
• Subtask 9: 9 / 9
• Subtask 10: 9 / 9
• Subtask 11: 10 / 10