oj.uz

답안 #649231

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
649231 2022-10-09T16:46:28 Z blue 수천개의 섬 (IOI22_islands) C++17
100 / 100
 141 ms 21872 KB 
#include "islands.h"
#include <bits/stdc++.h>
using namespace std;
 
using vi = vector<int>;
using pii = pair<int, int>;
using vpii = vector<pii>;
#define sz(x) int(x.size())
 
const int mx = 100'000;
 
vpii edge[mx];
vpii revedge[mx];
 
int N, M;
 
queue<int> tbv;
 
int src = 0;
 
vi pushed(mx, 0);
vi killed(mx, 0);
 
vi outdeg(mx, 0);
 
vi incedge(mx, -1);
 
void addvec(vi& a, vi& b)
{
	for(int u : b)
		a.push_back(u);
}
 
void rev(vi& a)
{
	reverse(a.begin(), a.end());
}
 
void addrev(vi& a, vi& b)
{
	rev(b);
	addvec(a, b);
	rev(b);
}
 
 
vi nodevis(mx, 0);
vi cyclic(mx, 0);
 
bool samecycle = 0;
 
 
vi lst1, nodelst1, cyc1, nodecyc1;
 
int bannededge;
 
 
void dfs1(int u)
{
	for(pii vp : edge[u])
	{
		int v = vp.first;
 
		if(killed[v])
			continue;
 
		if(nodevis[v] == 0)
		{
			lst1.push_back(vp.second);
			nodelst1.push_back(vp.first);
 
			if(u == src)
				bannededge = vp.second;
 
			nodevis[v] = 1;
			dfs1(v);
		}
		else if(nodevis[v] == 1)
		{
			// samecycle = 1;
			nodecyc1.push_back(v);
			cyclic[v] = 1;
			cyc1.push_back(vp.second);
 
			while(1)
			{
				if(nodelst1.back() == v)
					break;
 
				nodecyc1.push_back(nodelst1.back());
				cyclic[nodelst1.back()] = 1;
				cyc1.push_back(lst1.back());
 
				nodelst1.pop_back();
				lst1.pop_back();
 
				
			}
			rev(nodecyc1);
			rev(cyc1);
		}
		return;
	}
}
 
vi lst2, cyc2, nodelst2, nodecyc2;
 
void dfs2(int u)
{
	for(pii vp : edge[u])
	{
		if(vp.second == bannededge)
			continue;
 
		int v = vp.first;


		if(killed[v])
			continue;

 
		if(nodevis[v] == 0)
		{
			lst2.push_back(vp.second);
			nodelst2.push_back(vp.first);
 
			if(u == src)
				bannededge = vp.second;
 
			nodevis[v] = 2;
			dfs2(v);
		}
		else if(nodevis[v] == 2)
		{
			nodecyc2.push_back(v);
			cyc2.push_back(vp.second);

			while(1)
			{
				if(nodelst2.back() == v)
					break;
 
				nodecyc2.push_back(nodelst2.back());
				cyc2.push_back(lst2.back());
 
				nodelst2.pop_back();
				lst2.pop_back();
			}
			rev(nodecyc2);
			rev(cyc2);
		}
		else if(nodevis[v] == 1 && !cyclic[v])
		{
			samecycle = 1;
			nodecyc2 = nodecyc1;
			cyc2 = cyc1;

			// cerr << "no"

			int id = 0;
			while(nodelst1[id] != v)
				id++;

			nodelst2.push_back(v);
			lst2.push_back(vp.second);

			for(id++; id < sz(nodelst1); id++)
			{
				nodelst2.push_back(nodelst1[id]);
				lst2.push_back(lst1[id-1]);
			}
		}
		else if(nodevis[v] == 1 && cyclic[v])
		{
			samecycle = 1;
			lst2.push_back(vp.second);
 
			int z = 0;
			while(nodecyc1[z] != v)
				z++;
 
			for(int f = z+1; f < sz(cyc1); f++)
			{
				cyc2.push_back(cyc1[f]);
				nodecyc2.push_back(nodecyc1[f]);
			}
			for(int f = 0; f <= z; f++)
			{
				cyc2.push_back(cyc1[f]);
				nodecyc2.push_back(nodecyc1[f]);
			}
		}
		return;
	}
}
 
variant<bool, vi> find_journey(int N_, int M_, vi U, vi V)
{
	N = N_;
	M = M_;
 
	for(int j = 0; j < M; j++)
	{
		edge[U[j]].push_back({V[j], j});
		revedge[V[j]].push_back({U[j], j});
		outdeg[U[j]]++;
	}
 
	for(int i = 0; i < N; i++)
	{
		if(outdeg[i] == 0)
		{
			pushed[i] = 1;
			tbv.push(i);
		}
	}
 
	if(pushed[src])
	{
		return false;
	}
 
 
	vi originlist;
 
 
	while(1)
	{
		if(!tbv.empty())
		{
			int u = tbv.front();
			tbv.pop();
			killed[u] = 1;
 
			for(pii vp : revedge[u])
			{	
				int v = vp.first;
				outdeg[v]--;
				if(outdeg[v] == 0)
				{
					pushed[v] = 1;
					if(v == src)
					{
						// gettime();
						return false;
					}
					tbv.push(v);
				}
			}
		}
		else if(outdeg[src] == 1)
		{
			int newsrc;
			for(pii vp : edge[src])
			{
				if(!pushed[vp.first])
				{
					newsrc = vp.first;
					incedge[newsrc] = vp.second;
					originlist.push_back(vp.second);
					break;
				}
			}
 
 
			pushed[src] = 1;
			killed[src] = 1;
			for(pii vp : revedge[src])
			{
				int v = vp.first;
				if(vp.second == incedge[src])
					continue;

				outdeg[v]--;
				if(outdeg[v] == 0)
				{
					pushed[v] = 1;
					if(pushed[newsrc])
						return false;
					tbv.push(v);
				}
			}
 
			src = newsrc;
		}
		else
		{
			break;
		}
	}
 
 
 
	nodevis[src] = 1;
	nodelst1.push_back(src);
	dfs1(src);
 
 
	nodelst2.push_back(src);
	dfs2(src);

 
	vi res;
 
	if(!samecycle)
	{
		addvec(res, originlist);
 
		addvec(res, lst1);
		addvec(res, cyc1);
		addrev(res, lst1);
 
		addvec(res, lst2);
		addvec(res, cyc2);
		addrev(res, lst2);
 
		addvec(res, lst1);
		addrev(res, cyc1);
		addrev(res, lst1);
		
		addvec(res, lst2);
		addrev(res, cyc2);
		addrev(res, lst2);
 
		addrev(res, originlist);
	}
	else
	{
		addvec(res, originlist);
 
		addvec(res, lst1);
		addvec(res, cyc1);
		addrev(res, lst1);
 
		addvec(res, lst2);
		addrev(res, cyc2);
		addrev(res, lst2);
 
		addrev(res, originlist);
	}
	
	return res;
}

Compilation message

islands.cpp: In function 'std::variant<bool, std::vector<int, std::allocator<int> > > find_journey(int, int, vi, vi)':
islands.cpp:284:8: warning: 'newsrc' may be used uninitialized in this function [-Wmaybe-uninitialized]
  284 |    src = newsrc;
      |    ~~~~^~~~~~~~

Subtask #1
5.0 / 5.0

# 결과 실행 시간 메모리 Grader output
1 Correct 4 ms 7252 KB Output is correct
2 Correct 4 ms 7252 KB Output is correct
3 Correct 4 ms 7336 KB Output is correct
4 Correct 5 ms 7252 KB Output is correct
5 Correct 4 ms 7252 KB Output is correct
6 Correct 4 ms 7252 KB Output is correct
7 Correct 43 ms 13648 KB Output is correct

Subtask #2
5.0 / 5.0

# 결과 실행 시간 메모리 Grader output
1 Correct 4 ms 7252 KB Output is correct
2 Correct 4 ms 7252 KB Output is correct
3 Correct 4 ms 7252 KB Output is correct
4 Correct 6 ms 7280 KB Output is correct
5 Correct 4 ms 7252 KB Output is correct
6 Correct 38 ms 13332 KB Output is correct

Subtask #3
21.0 / 21.0

# 결과 실행 시간 메모리 Grader output
1 Correct 5 ms 7508 KB Output is correct
2 Correct 5 ms 7252 KB Output is correct
3 Correct 4 ms 7268 KB Output is correct
4 Correct 4 ms 7252 KB Output is correct
5 Correct 5 ms 7380 KB Output is correct
6 Correct 5 ms 7252 KB Output is correct
7 Correct 6 ms 7380 KB Output is correct
8 Correct 4 ms 7280 KB Output is correct
9 Correct 4 ms 7380 KB Output is correct
10 Correct 5 ms 7380 KB Output is correct
11 Correct 4 ms 7352 KB Output is correct
12 Correct 5 ms 7380 KB Output is correct
13 Correct 4 ms 7252 KB Output is correct
14 Correct 4 ms 7252 KB Output is correct
15 Correct 4 ms 7252 KB Output is correct
16 Correct 4 ms 7252 KB Output is correct
17 Correct 28 ms 11176 KB Output is correct
18 Correct 22 ms 10836 KB Output is correct
19 Correct 4 ms 7252 KB Output is correct
20 Correct 4 ms 7252 KB Output is correct
21 Correct 5 ms 7252 KB Output is correct
22 Correct 4 ms 7252 KB Output is correct
23 Correct 40 ms 13260 KB Output is correct

Subtask #4
24.0 / 24.0

# 결과 실행 시간 메모리 Grader output
1 Correct 5 ms 7252 KB Output is correct
2 Correct 5 ms 7508 KB Output is correct
3 Correct 40 ms 13772 KB Output is correct
4 Correct 56 ms 14388 KB Output is correct
5 Correct 5 ms 7508 KB Output is correct
6 Correct 5 ms 7508 KB Output is correct
7 Correct 4 ms 7252 KB Output is correct
8 Correct 4 ms 7252 KB Output is correct
9 Correct 4 ms 7252 KB Output is correct
10 Correct 5 ms 7508 KB Output is correct
11 Correct 7 ms 7508 KB Output is correct
12 Correct 5 ms 7496 KB Output is correct
13 Correct 6 ms 7636 KB Output is correct
14 Correct 6 ms 7528 KB Output is correct
15 Correct 5 ms 7508 KB Output is correct
16 Correct 5 ms 7380 KB Output is correct
17 Correct 5 ms 7252 KB Output is correct
18 Correct 5 ms 7508 KB Output is correct
19 Correct 4 ms 7380 KB Output is correct
20 Correct 42 ms 15052 KB Output is correct
21 Correct 42 ms 14540 KB Output is correct
22 Correct 5 ms 7380 KB Output is correct
23 Correct 4 ms 7380 KB Output is correct
24 Correct 4 ms 7380 KB Output is correct
25 Correct 5 ms 7380 KB Output is correct
26 Correct 5 ms 7544 KB Output is correct
27 Correct 45 ms 14660 KB Output is correct
28 Correct 43 ms 14732 KB Output is correct
29 Correct 4 ms 7252 KB Output is correct
30 Correct 48 ms 15824 KB Output is correct
31 Correct 4 ms 7252 KB Output is correct
32 Correct 45 ms 14784 KB Output is correct
33 Correct 46 ms 14468 KB Output is correct
34 Correct 25 ms 11152 KB Output is correct
35 Correct 5 ms 7380 KB Output is correct
36 Correct 38 ms 13796 KB Output is correct
37 Correct 44 ms 15456 KB Output is correct
38 Correct 5 ms 7380 KB Output is correct
39 Correct 38 ms 13940 KB Output is correct
40 Correct 7 ms 7380 KB Output is correct
41 Correct 50 ms 15836 KB Output is correct
42 Correct 42 ms 14864 KB Output is correct
43 Correct 4 ms 7252 KB Output is correct
44 Correct 5 ms 7508 KB Output is correct
45 Correct 5 ms 7508 KB Output is correct
46 Correct 22 ms 10688 KB Output is correct

Subtask #5
45.0 / 45.0

# 결과 실행 시간 메모리 Grader output
1 Correct 4 ms 7252 KB Output is correct
2 Correct 4 ms 7252 KB Output is correct
3 Correct 4 ms 7336 KB Output is correct
4 Correct 5 ms 7252 KB Output is correct
5 Correct 4 ms 7252 KB Output is correct
6 Correct 4 ms 7252 KB Output is correct
7 Correct 43 ms 13648 KB Output is correct
8 Correct 4 ms 7252 KB Output is correct
9 Correct 4 ms 7252 KB Output is correct
10 Correct 4 ms 7252 KB Output is correct
11 Correct 6 ms 7280 KB Output is correct
12 Correct 4 ms 7252 KB Output is correct
13 Correct 38 ms 13332 KB Output is correct
14 Correct 5 ms 7508 KB Output is correct
15 Correct 5 ms 7252 KB Output is correct
16 Correct 4 ms 7268 KB Output is correct
17 Correct 4 ms 7252 KB Output is correct
18 Correct 5 ms 7380 KB Output is correct
19 Correct 5 ms 7252 KB Output is correct
20 Correct 6 ms 7380 KB Output is correct
21 Correct 4 ms 7280 KB Output is correct
22 Correct 4 ms 7380 KB Output is correct
23 Correct 5 ms 7380 KB Output is correct
24 Correct 4 ms 7352 KB Output is correct
25 Correct 5 ms 7380 KB Output is correct
26 Correct 4 ms 7252 KB Output is correct
27 Correct 4 ms 7252 KB Output is correct
28 Correct 4 ms 7252 KB Output is correct
29 Correct 4 ms 7252 KB Output is correct
30 Correct 28 ms 11176 KB Output is correct
31 Correct 22 ms 10836 KB Output is correct
32 Correct 4 ms 7252 KB Output is correct
33 Correct 4 ms 7252 KB Output is correct
34 Correct 5 ms 7252 KB Output is correct
35 Correct 4 ms 7252 KB Output is correct
36 Correct 40 ms 13260 KB Output is correct
37 Correct 4 ms 7252 KB Output is correct
38 Correct 4 ms 7252 KB Output is correct
39 Correct 4 ms 7380 KB Output is correct
40 Correct 4 ms 7380 KB Output is correct
41 Correct 22 ms 10636 KB Output is correct
42 Correct 7 ms 7532 KB Output is correct
43 Correct 49 ms 12432 KB Output is correct
44 Correct 49 ms 12360 KB Output is correct
45 Correct 60 ms 12380 KB Output is correct
46 Correct 4 ms 7264 KB Output is correct
47 Correct 4 ms 7252 KB Output is correct
48 Correct 4 ms 7252 KB Output is correct
49 Correct 5 ms 7508 KB Output is correct
50 Correct 123 ms 21544 KB Output is correct
51 Correct 118 ms 17532 KB Output is correct
52 Correct 97 ms 17484 KB Output is correct
53 Correct 95 ms 17480 KB Output is correct
54 Correct 106 ms 17500 KB Output is correct
55 Correct 117 ms 17480 KB Output is correct
56 Correct 98 ms 17488 KB Output is correct
57 Correct 68 ms 15904 KB Output is correct
58 Correct 108 ms 21712 KB Output is correct
59 Correct 109 ms 17508 KB Output is correct
60 Correct 96 ms 16972 KB Output is correct
61 Correct 98 ms 17248 KB Output is correct
62 Correct 22 ms 9372 KB Output is correct
63 Correct 89 ms 17028 KB Output is correct
64 Correct 28 ms 11596 KB Output is correct
65 Correct 4 ms 7252 KB Output is correct
66 Correct 5 ms 7380 KB Output is correct
67 Correct 141 ms 17496 KB Output is correct
68 Correct 54 ms 15820 KB Output is correct
69 Correct 73 ms 13364 KB Output is correct
70 Correct 5 ms 7508 KB Output is correct
71 Correct 82 ms 14424 KB Output is correct
72 Correct 4 ms 7252 KB Output is correct
73 Correct 85 ms 16852 KB Output is correct
74 Correct 106 ms 21872 KB Output is correct
75 Correct 8 ms 7764 KB Output is correct
76 Correct 52 ms 13968 KB Output is correct
77 Correct 66 ms 15208 KB Output is correct
78 Correct 131 ms 17236 KB Output is correct
79 Correct 4 ms 7252 KB Output is correct
80 Correct 126 ms 21420 KB Output is correct
81 Correct 5 ms 7508 KB Output is correct
82 Correct 41 ms 14268 KB Output is correct
83 Correct 5 ms 7380 KB Output is correct
84 Correct 6 ms 7252 KB Output is correct
85 Correct 45 ms 14640 KB Output is correct
86 Correct 5 ms 7380 KB Output is correct
87 Correct 7 ms 7764 KB Output is correct
88 Correct 7 ms 7508 KB Output is correct
89 Correct 106 ms 16984 KB Output is correct
90 Correct 102 ms 17264 KB Output is correct
91 Correct 118 ms 21812 KB Output is correct
92 Correct 4 ms 7252 KB Output is correct