Submission #613719

#	Time	Username	Problem	Language	Result	Execution time	Memory
613719		Red_Inside	Fountain Parks (IOI21_parks)	C++17	5 / 100	542 ms	101140 KiB

parks

#include "parks.h"
//
#include <bits/stdc++.h>

#define ll long long
#define f first
#define s second
#define pb push_back
#define mp make_pair
#define o cout<<"BUG"<<endl;
#define FOR(i, j, n) for(int j = i; j < n; ++j)
#define forn(i, j, n) for(int j = i; j <= n; ++j)
#define nfor(i, j, n) for(int j = n; j >= i; --j)
#define all(v) v.begin(), v.end()
#define ld long double
#define ull unsigned long long

using namespace std;
const int maxn=2e5+100,LOG=17,mod=1e9+7;
int block = 226, timer = 0;
const ld EPS = 1e-18;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
#define IOS ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);

#define bt(i) (1 << (i))
//#define int ll
const int inf=2e9;
#define y1 yy
#define prev pre
#define pii pair <int, int>

int used[maxn], mt[maxn], to[maxn][3];
vector <int> edge[maxn];
map <int, int> mapp[maxn];
vector <pii> vec, edges;

void dfs(int v)
{
	used[v] = 1;
	shuffle(all(edge[v]), rng);
	for(auto to : edge[v])
	{
		if(!used[to])
		{
			edges.pb({v, to});
			dfs(to);
		}
	}
}

int try_kuhn(int v)
{
	if(used[v] == timer) return 0;
	used[v] = timer;
	if(mt[to[v][0]] == -1)
	{
		mt[to[v][0]] = v;
		return 1;
	}
	if(mt[to[v][1]] == -1)
	{
		mt[to[v][1]] = v;
		return 1;
	}
	if(try_kuhn(mt[to[v][0]]))
	{
		mt[to[v][0]] = v;
		return 1;
	}
	if(try_kuhn(mt[to[v][1]]))
	{
		mt[to[v][1]] = v;
		return 1;
	}
	return 0;
}

int construct_roads(vector <int> x, vector <int> y)
{
	int n = x.size();
	forn(0, i, n-1)
	{
		mapp[x[i]][y[i]] = i;
	}
	forn(0, i, n-1)
	{
		if(mapp[x[i]].count(y[i] - 2))
		{
			edge[i].pb(mapp[x[i]][y[i]-2]);
		}
		if(mapp[x[i]].count(y[i] + 2))
		{
			edge[i].pb(mapp[x[i]][y[i]+2]);
		}
		if(mapp[x[i]+2].count(y[i]))
		{
			edge[i].pb(mapp[x[i]+2][y[i]]);
		}
		if(mapp[x[i]-2].count(y[i]))
		{
			edge[i].pb(mapp[x[i]-2][y[i]]);
		}
	}
	int start = 0;
	forn(1, i, n-1)
	{
		if(x[i] < x[start]) start = i;
		else if(x[i] == x[start] && y[i] > y[start]) start = i;
	}
	dfs(start);
	forn(0, i, n-1)
	{
		if(!used[i]) return 0;
	}
	for(auto i : edges)
	{
		if(y[i.f] == y[i.s])
		{
			vec.pb({max(x[i.f], x[i.s])-1, y[i.f] - 1});
			vec.pb({max(x[i.f], x[i.s])-1, y[i.f] + 1});
		}
		else
		{
			vec.pb({x[i.f] - 1, max(y[i.f], y[i.s]) - 1});
			vec.pb({x[i.f] + 1, max(y[i.f], y[i.s]) - 1});
		}
	}
	sort(all(vec));
	vec.erase(unique(all(vec)), vec.end());
//	FOR(0, i, vec.size()) cout << vec[i].f << "   " << vec[i].s << endl;
	FOR(0, it, edges.size())
	{
		pii i = edges[it];
		if(y[i.f] == y[i.s])
		{
			to[it][0] = lower_bound(all(vec), mp(max(x[i.f], x[i.s])-1, y[i.f] - 1))-vec.begin();
			to[it][1] = lower_bound(all(vec), mp(max(x[i.f], x[i.s])-1, y[i.f] + 1))-vec.begin();
		}
		else
		{
			to[it][0] = lower_bound(all(vec), mp(x[i.f] - 1, max(y[i.f], y[i.s]) - 1))-vec.begin();
			to[it][1] = lower_bound(all(vec), mp(x[i.f] + 1, max(y[i.f], y[i.s]) - 1))-vec.begin();
		}
//		cout << "E " << edges[it].f << " " << edges[it].s << " " << to[it][0] << " " << to[it][1] << endl;
	}
	FOR(0, i, vec.size()) mt[i] = -1;
	
	FOR(0, j, edges.size()) used[j] = 0;
	FOR(0, i, edges.size())
	{
		++timer;
		try_kuhn(i);
	}
	/*while(true)
	{
		cout << "GO\n";
		int ok = 0;
		FOR(0, i, edges.size()) used[i] = 0;
		FOR(0, i, edges.size())
		{
			if(used[i]) continue;
			if(try_kuhn(i))
			{
				ok = 1;
			}
		}
		if(!ok) break;
	}*/
	vector <int> ans1, ans2, ans3, ans4;
	for(auto i : edges)
	{
		ans1.pb(i.f);
		ans2.pb(i.s);
	}
	ans3.assign(edges.size(), 0);
	ans4.assign(edges.size(), 0);
	FOR(0, i, vec.size())
	{
		if(mt[i] == -1) continue;
		ans3[mt[i]] = vec[i].f;
		ans4[mt[i]] = vec[i].s;
	}
	build(ans1, ans2, ans3, ans4);
	return 1;
}

Compilation message (stderr)

parks.cpp: In function 'int construct_roads(std::vector<int>, std::vector<int>)':
parks.cpp:11:39: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   11 | #define FOR(i, j, n) for(int j = i; j < n; ++j)
......
  131 |  FOR(0, it, edges.size())
      |         ~~~~~~~~~~~~~~~~               
parks.cpp:131:2: note: in expansion of macro 'FOR'
  131 |  FOR(0, it, edges.size())
      |  ^~~
parks.cpp:11:39: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   11 | #define FOR(i, j, n) for(int j = i; j < n; ++j)
......
  146 |  FOR(0, i, vec.size()) mt[i] = -1;
      |         ~~~~~~~~~~~~~                  
parks.cpp:146:2: note: in expansion of macro 'FOR'
  146 |  FOR(0, i, vec.size()) mt[i] = -1;
      |  ^~~
parks.cpp:11:39: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   11 | #define FOR(i, j, n) for(int j = i; j < n; ++j)
......
  148 |  FOR(0, j, edges.size()) used[j] = 0;
      |         ~~~~~~~~~~~~~~~                
parks.cpp:148:2: note: in expansion of macro 'FOR'
  148 |  FOR(0, j, edges.size()) used[j] = 0;
      |  ^~~
parks.cpp:11:39: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   11 | #define FOR(i, j, n) for(int j = i; j < n; ++j)
......
  149 |  FOR(0, i, edges.size())
      |         ~~~~~~~~~~~~~~~                
parks.cpp:149:2: note: in expansion of macro 'FOR'
  149 |  FOR(0, i, edges.size())
      |  ^~~
parks.cpp:11:39: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   11 | #define FOR(i, j, n) for(int j = i; j < n; ++j)
......
  177 |  FOR(0, i, vec.size())
      |         ~~~~~~~~~~~~~                  
parks.cpp:177:2: note: in expansion of macro 'FOR'
  177 |  FOR(0, i, vec.size())
      |  ^~~

• Subtask 1: 5 / 5
• Subtask 2: 0 / 10
• Subtask 3: 0 / 15
• Subtask 4: 0 / 20
• Subtask 5: 0 / 20
• Subtask 6: 0 / 30