Submission #941134

#	Time	Username	Problem	Language	Result	Execution time	Memory
941134		FKS	Martian DNA (BOI18_dna)	C++14	100 / 100	139 ms	16768 KiB

dna

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

#define max(a, b) (a > b ? a : b)

int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	
	int n, k, r;cin>>n>>k>>r;
	int* dna = new int[n];
	for (int i = 0;i < n;i++)
		cin >> dna[i];

	unordered_set<int> hset;
	unordered_map<int, int> req;
	unordered_set<int> sreq;
	for (int i = 0;i < r;i++)
	{
		int x, y;
		cin >> x >> y;

		hset.emplace(x);
		req[x] = y;
		sreq.emplace(x);
	}

	int min_len = 1e9;
	int j = -1;
	for (int i = 0;i < n;i++)
	{
		if (i && hset.count(dna[i-1]))
		{
			req[dna[i-1]]++;
			if (req[dna[i-1]] > 0)
				sreq.emplace(dna[i-1]);
		}

		if (sreq.size())
			for (j=j+1;j < n;j++)
			{
				if (hset.count(dna[j]))
				{
					req[dna[j]]--;
					if (req[dna[j]] <= 0)
						sreq.erase(dna[j]);
				}

				if (!sreq.size()) {
					min_len = min(min_len, j - i + 1);
					break;
				}
			}
		else

					min_len = min(min_len, j - i + 1);
	}


	if (min_len == 1e9)
		cout << "impossible";
	else if (min_len)
		cout << min_len;
	else if (min_len == 0)
		cout << "impossible";

	return 0;
}

• Subtask 1: 16 / 16
• Subtask 2: 24 / 24
• Subtask 3: 28 / 28
• Subtask 4: 32 / 32