oj.uz

Submission #483496

# Submission time Handle Problem Language Result Execution time Memory
483496 2021-10-30T04:26:56 Z blue Sky Walking (IOI19_walk) C++17
10 / 100
 4000 ms 281124 KB 
#include "walk.h"
#include <vector>
#include <set>
#include <iostream>
#include <algorithm>
#include <cassert>
using namespace std;

int N;
vector<int> X;
vector<int> H;

int M;
vector<int> L;
vector<int> R;
vector<int> Y;

int S;
int G;


int ht(int i)
{
	if(i > 0) return H[i-1];
	else return Y[-i-1];
}

bool cmp(int i, int j)
{
	if(ht(i) == ht(j)) return i > j;
	else return ht(i) > ht(j);
}


vector<int> newL, newR, newY;




const int mx = 4'000'000;
const long long INF = 1'000'000'000'000'000'000LL;


vector<int> edge[mx];
vector<long long> wt[mx];

void add_edge(int u, int v, long long w)
{
	cerr << "add edge " << u << ' ' << v << ' ' << w << '\n';
	edge[u].push_back(v);
	wt[u].push_back(w);

	edge[v].push_back(u);
	wt[v].push_back(w);
}

vector<long long> distS(mx, INF);

struct distcomp
{
	int i;
};

bool operator < (distcomp A, distcomp B)
{
	if(distS[A.i] == distS[B.i]) return A.i < B.i;
	return distS[A.i] < distS[B.i];
}


set<pair<int, int> > points;  //stored by building index + y coordinate







struct loc
{
	int b;
	int y;

	int ind;
};

bool operator < (loc A, loc B)
{
	if(A.y == B.y) return A.b < B.b;
	else return A.y < B.y;
}



long long min_distance(vector<int> x, vector<int> h, vector<int> l, vector<int> r, vector<int> y, int s, int g)
{
	N = int(x.size());
	X = x;
	H = h;

	M = int(l.size());
	L = l;
	R = r;
	Y = y;

	S = s;
	G = g;



	vector<int> obj;
	for(int i = 0; i < N; i++) obj.push_back(i+1);
	for(int j = 0; j < M; j++) obj.push_back(-(j+1));
	sort(obj.begin(), obj.end(), cmp);

	vector<int> walk_buildings[M];

	set<int> buildings;
	for(int o: obj)
	{
		if(o > 0)
		{
			buildings.insert(o-1);
		}
		else
		{
			int w = -o-1;
			set<int> endpoints;
			endpoints.insert(L[w]);
			endpoints.insert(R[w]);
			points.insert(make_pair(L[w], Y[w]));
			cerr << "inserting point A " << L[w] << ' ' << Y[w] << '\n';
			points.insert(make_pair(R[w], Y[w]));
			cerr << "inserting point B " << R[w] << ' ' << Y[w] << '\n';
			walk_buildings[w].push_back(L[w]);
			walk_buildings[w].push_back(R[w]);

			for(int z: {s, g})
			{
				auto f = buildings.lower_bound(z);
				if(f != buildings.end())
					if(L[w] < *f && *f < R[w])
					{
						points.insert(make_pair(*f, Y[w]));
						cerr << "inserting point C " << *f << ' ' << Y[w] << '\n';
						walk_buildings[w].push_back(*f);
					}
						// endpoints.insert(*f);

				if(f != buildings.begin())
				{
					f--;
					if(L[w] < *f && *f < R[w])
					{
						points.insert(make_pair(*f, Y[w]));
						cerr << "inserting point D " << *f << ' ' << Y[w] << '\n';
						walk_buildings[w].push_back(*f);
					}
				}
			}
		}
	}

	vector<int> ep[N];

	for(int j = 0; j < M; j++)
	{
		walk_buildings[j].erase(unique(walk_buildings[j].begin(), walk_buildings[j].end()), walk_buildings[j].end());
		for(int i: walk_buildings[j])
			ep[i].push_back(j);
	}

	points.insert(make_pair(S, 0));
	points.insert(make_pair(G, 0));


	vector<int> left_ep[N], right_ep[N];
	for(int j = 0; j < M; j++)
	{
		left_ep[L[j]].push_back(j);
		right_ep[R[j]].push_back(j);
	}

	set< pair<int, int> > curr_walks;
	for(int i = 0; i < N; i++)
	{
		for(int w: left_ep[i])
		{
			curr_walks.insert(make_pair(Y[w], w));
		}

		for(int w: ep[i])
		{
			auto f = curr_walks.find(make_pair(Y[w], w));
			assert(f != curr_walks.end());
			auto f1 = f;

			if(f != curr_walks.begin())
			{
				f--;
				if(L[f->second] <= i && i <= R[f->second] && Y[f->second] <= H[i])
					points.insert(make_pair(i, f->first));
				// cerr << "inserting point " << *f << ' ' << Y[w] << '\n';
			}

			if(f1 != curr_walks.end())
			{
				f1++;
				if(f1 != curr_walks.end())
					if(L[f1->second] <= i && i <= R[f1->second] && Y[f1->second] <= H[i])
						points.insert(make_pair(i, f1->first));
			}
		}

		for(int w: right_ep[i])
		{
			curr_walks.erase(make_pair(Y[w], w));
		}
	}

		cerr << "all points: ";
		for(auto p:points) cerr << p.first << ' ' << p.second << '\n';

	vector<loc> places;

	int ct = -1;
	for(auto p: points)
	{
		ct++;
		places.push_back(loc{p.first, p.second, ct});
	}

	sort(places.begin(), places.end(), [] (loc k, loc l)
	{
		if(k.b == l.b)
			return k.y < l.y;
		else
			return k.b < l.b;
	});

	cerr << "vertical edges: \n";

	for(int i = 0; i+1 < int(places.size()); i++)
	{
		if(places[i].b == places[i+1].b)
			add_edge(places[i].ind, places[i+1].ind, places[i+1].y - places[i].y);
	}

	sort(places.begin(), places.end(), [] (loc k, loc l)
	{
		if(k.y == l.y)
			return k.b < l.b;
		else
			return k.y < l.y;
	});

	cerr << "horiz edges: \n";

	cerr << "\n\n\n\nsorted places: \n";
	for(auto q: places) cerr << q.b << ' ' << q.y << ' ' << q.ind << '\n';
	cerr << "\n\n\n";

	for(int j = 0; j < M; j++)
	{
		cerr << "j = " << j << '\n';
		auto f = lower_bound(places.begin(), places.end(), loc{L[j], Y[j], -1});
		auto g = f;
		g++;

		int ite = 0;

		while(1)
		{
			cerr << "ite = " << ite << '\n';
			ite++;
			cerr << int(g == places.end()) << '\n';
			if(g == places.end()) break;
			if(g->b > R[j]) break;
			if(g->y != Y[j]) break;
			// cerr << "gb = " << g->b << ", fb = " << f->b << '\n';
			cerr << "g = " << g->b << ' ' << g->y << ", " << "f = " << f->b << ' ' << f->y << '\n';
			add_edge(f->ind, g->ind, X[g->b] - X[f->b]);
			f++;
			g++;
			cerr << "done\n";
		}
	}
	cerr << "j done\n";

	int S_loc, G_loc;

	for(int i = 0; i <= ct; i++)
	{
		if(places[i].b == S && places[i].y == 0)
			S_loc = places[i].ind;
		else if(places[i].b == G && places[i].y == 0)
			G_loc = places[i].ind;
	}


	for(int i = 0; i <= ct; i++) cerr << "position " << places[i].b << ' ' << places[i].y << " = index " << places[i].ind << '\n';


	distS[S_loc] = 0;

	set<distcomp> tbv;
	for(int i = 0; i <= ct; i++)
		tbv.insert(distcomp{i});

	cerr << "hello\n";


	while(!tbv.empty())
	{
		int u = tbv.begin()->i;
		tbv.erase(tbv.begin());

		cerr << "u = " << u << ", distS = " << distS[u] << '\n';

		for(int e = 0; e < int(edge[u].size()); e++)
		{
			int v = edge[u][e];
			long long w = wt[u][e];

			if(distS[v] <= distS[u] + w) continue;
			tbv.erase(distcomp{v});
			distS[v] = distS[u] + w;
			tbv.insert(distcomp{v});
		}
	}

	if(distS[G_loc] >= INF)
		distS[G_loc] = -1;

	return distS[G_loc];
}

Compilation message

walk.cpp: In function 'long long int min_distance(std::vector<int>, std::vector<int>, std::vector<int>, std::vector<int>, std::vector<int>, int, int)':
walk.cpp:304:13: warning: 'S_loc' may be used uninitialized in this function [-Wmaybe-uninitialized]
  304 |  distS[S_loc] = 0;
      |             ^
walk.cpp:332:16: warning: 'G_loc' may be used uninitialized in this function [-Wmaybe-uninitialized]
  332 |  if(distS[G_loc] >= INF)
      |                ^

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 111 ms 219460 KB Output is correct
2 Correct 110 ms 219508 KB Output is correct
3 Correct 110 ms 219444 KB Output is correct
4 Correct 107 ms 219460 KB Output is correct
5 Correct 122 ms 219588 KB Output is correct
6 Correct 119 ms 219528 KB Output is correct
7 Correct 125 ms 219564 KB Output is correct
8 Correct 118 ms 219564 KB Output is correct
9 Correct 113 ms 219460 KB Output is correct
10 Correct 129 ms 219488 KB Output is correct
11 Correct 121 ms 219416 KB Output is correct
12 Correct 116 ms 219404 KB Output is correct
13 Correct 115 ms 219496 KB Output is correct
14 Correct 111 ms 219476 KB Output is correct
15 Correct 112 ms 219420 KB Output is correct
16 Correct 123 ms 219412 KB Output is correct
17 Correct 120 ms 219464 KB Output is correct

Subtask #2
0 / 14.0

# Verdict Execution time Memory Grader output
1 Correct 108 ms 219480 KB Output is correct
2 Correct 108 ms 219384 KB Output is correct
3 Execution timed out 4112 ms 281124 KB Time limit exceeded
4 Halted 0 ms 0 KB -

Subtask #3
0 / 15.0

# Verdict Execution time Memory Grader output
1 Execution timed out 4108 ms 251620 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #4
0 / 18.0

# Verdict Execution time Memory Grader output
1 Execution timed out 4108 ms 251620 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #5
0 / 43.0

# Verdict Execution time Memory Grader output
1 Correct 111 ms 219460 KB Output is correct
2 Correct 110 ms 219508 KB Output is correct
3 Correct 110 ms 219444 KB Output is correct
4 Correct 107 ms 219460 KB Output is correct
5 Correct 122 ms 219588 KB Output is correct
6 Correct 119 ms 219528 KB Output is correct
7 Correct 125 ms 219564 KB Output is correct
8 Correct 118 ms 219564 KB Output is correct
9 Correct 113 ms 219460 KB Output is correct
10 Correct 129 ms 219488 KB Output is correct
11 Correct 121 ms 219416 KB Output is correct
12 Correct 116 ms 219404 KB Output is correct
13 Correct 115 ms 219496 KB Output is correct
14 Correct 111 ms 219476 KB Output is correct
15 Correct 112 ms 219420 KB Output is correct
16 Correct 123 ms 219412 KB Output is correct
17 Correct 120 ms 219464 KB Output is correct
18 Correct 108 ms 219480 KB Output is correct
19 Correct 108 ms 219384 KB Output is correct
20 Execution timed out 4112 ms 281124 KB Time limit exceeded
21 Halted 0 ms 0 KB -