Submission #466233

#	Time	Username	Problem	Language	Result	Execution time	Memory
466233		prvocislo	Exercise Deadlines (CCO20_day1problem2)	C++17	25 / 25	145 ms	7112 KiB

Main

#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include <queue>
typedef long long ll;
using namespace std;

const int maxn = 1 << 18;
int maxi[maxn * 2], alive[maxn * 2];
void merge(int i)
{
	maxi[i] = max(maxi[i << 1], maxi[i << 1 | 1]);
	alive[i] = alive[i << 1] + alive[i << 1 | 1];
}
void remove_element(int i)
{
	i += maxn;
	maxi[i] = -1, alive[i] = 0;
	for (i = (i >> 1); i > 0; i >>= 1) merge(i);
}
int last_big(int x)
{
	int i = 1;
	for (; i < maxn; )
	{
		if (maxi[i << 1 | 1] < x) i = i << 1;
		else i = i << 1 | 1;
	}
	return i - maxn;
}
int sum(int l, int r)
{
	int s = 0;
	for (l += maxn, r += maxn + 1; l < r; l >>= 1, r >>= 1)
	{
		if (l & 1) s += alive[l++];
		if (r & 1) s += alive[--r];
	}
	return s;
}
int main()
{
	ios::sync_with_stdio(false);
	cin.tie(0);
	for (int i = 0; i < maxn * 2; i++) maxi[i] = -1;
	int n;
	cin >> n;
	vector<int> d(n);
	for (int i = 0; i < n; i++) cin >> d[i], maxi[i + maxn] = --d[i], alive[i + maxn] = 1;
	for (int i = maxn - 1; i > 0; i--) merge(i);
	vector<int> v = d;
	sort(v.begin(), v.end());
	for (int i = 0; i < n; i++) if (v[i] < i)
	{
		cout << "-1\n";
		return 0;
	}
	ll ans = 0;
	for (int i = n - 1; i >= 0; i--)
	{
		int j = last_big(i);
		//cout << j << endl;
		ans += sum(j, n - 1) - 1;
		remove_element(j);
	}
	cout << ans << "\n";
	return 0;
}

• Subtask 1: 17 / 17
• Subtask 2: 8 / 8