Submission #471858

#	Time	Username	Problem	Language	Result	Execution time	Memory
471858		prvocislo	Lamps (JOI19_lamps)	C++17	100 / 100	883 ms	113964 KiB

lamp

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

const int inf = 1e9 + 5, di = 3, cnt = 1 << (2 * di);
void upd(int& a, const int& b) { a = min(a, b); }
int main()
{
	ios::sync_with_stdio(false);
	cin.tie(0);
	int n;
	string sa, sb;
	cin >> n >> sa >> sb;
	vector<int> a, b;
	for (int i = 0; i < n; i++) a.push_back(sa[i] == '1');
	for (int i = 0; i < n; i++) b.push_back(sb[i] == '1');
	vector<int> c(cnt), v, num(cnt, -1);
	for (int i = 0; i < cnt; i++)
	{
		int k = 0;
		vector<int> f(4);
		for (int j = 0; j < di; j++)
		{
			int val = (i >> (2 * j)) & 3;
			if (val) c[i] |= val << (k * 2), k++, f[val]++;
		}
		if (*max_element(f.begin(), f.end()) <= 1 && c[i] == i) 
			num[i] = v.size(), v.push_back(i);
	}
	vector<vector<int> > dp(n + 1, vector<int>(v.size(), inf));
	dp[0][0] = 0;
	for (int i = 0; i < n; i++)
	{
		// ideme ukoncit par zmien - naraz vzdy len jednu
		for (int j = v.size() - 1; j >= 0; j--) for (int k = 0; k < di; k++)
		{
			int mask = (cnt - 1) ^ (3 << (2 * k)), nw = num[c[mask & v[j]]];
			if (nw != -1) upd(dp[i][nw], dp[i][j]);
		}
		// ideme vytvorit par zmien
		for (int j = 0; j < v.size(); j++) for (int k = 0; k < di; k++)
		{
			int mask = (cnt - 1) ^ (3 << (2 * k)), nw = num[c[mask & v[j]]];
			if (nw != -1) upd(dp[i][j], dp[i][nw] + 1);
		}
		// ideme na dalsi prvok
		for (int j = 0; j < v.size(); j++)
		{
			int val = a[i];
			for (int k = 0; k < di; k++)
			{
				int d = (v[j] >> (2 * k)) & 3;
				if (d == 1) val = !val;
				if (d == 2) val = 0;
				if (d == 3) val = 1;
			}
			if (val == b[i]) upd(dp[i + 1][j], dp[i][j]);
		}
	}
	int ans = inf;
	for (int i = 0; i < v.size(); i++) upd(ans, dp[n][i]);
	cout << ans << "\n";
	return 0;
}

Compilation message (stderr)

lamp.cpp: In function 'int main()':
lamp.cpp:46:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   46 |   for (int j = 0; j < v.size(); j++) for (int k = 0; k < di; k++)
      |                   ~~^~~~~~~~~~
lamp.cpp:52:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   52 |   for (int j = 0; j < v.size(); j++)
      |                   ~~^~~~~~~~~~
lamp.cpp:66:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   66 |  for (int i = 0; i < v.size(); i++) upd(ans, dp[n][i]);
      |                  ~~^~~~~~~~~~

• Subtask 1: 6 / 6
• Subtask 2: 41 / 41
• Subtask 3: 4 / 4
• Subtask 4: 49 / 49