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Submission #1044378

# Submission time Handle Problem Language Result Execution time Memory
1044378 2024-08-05T09:06:38 Z 김은성(#11005) Parking (CEOI22_parking) C++17
60 / 100
 288 ms 60284 KB 
#include <bits/stdc++.h>
using namespace std;
bool ch[500009];
vector<pair<int, int> > graph[500009];
int b0[500009], t0[500009], b[500009], t[500009];
unordered_set<int> emp;
vector<int> color[500009];
vector<pair<int, int> > ans;
vector<int> comp, cols;
vector<pair<int, int> > res;
bool done[500009];
bool solo[500009];
int needed = 0;
void dfs(int v){
	ch[v] = 1;
	cols.push_back(v);
	for(auto [e, u]: graph[v]){
		comp.push_back(e);
		if(!ch[u]){
			dfs(u);
		}
	}
}
void makemove(int occ, int e){
	//printf("from=%d to=%d\n", occ, e);
	needed = min((int)emp.size(), needed);
	ans.push_back(make_pair(occ, e));
	if(t[occ]){
		color[t[occ]].erase(find(color[t[occ]].begin(), color[t[occ]].end(), occ));
		color[b[occ]].push_back(occ);
		if(b[e]){
			t[e] = t[occ];
			t[occ] = 0;
		}
		else{
			b[e] = t[occ];
			t[occ] = 0;
			emp.erase(e);
			color[b[e]].push_back(e);
		}
	}
	else{
		color[b[occ]].erase(find(color[b[occ]].begin(), color[b[occ]].end(), occ));
		emp.insert(occ);
		if(b[e]){
			t[e] = b[occ];
			b[occ] = 0;
		}
		else{
			b[e] = b[occ];
			b[occ] = 0;
			emp.erase(e);
			color[b[e]].push_back(e);
		}
	}
	needed = min((int)emp.size(), needed);
}
int main(){
	int n, m, i, j, ans2 = 0;
	bool flag = 0;
	scanf("%d %d", &n, &m);
	//assert(m<=4);
	for(i=1; i<=m; i++){
		scanf("%d %d", &b[i], &t[i]);
		b0[i] = b[i];
		t0[i] = t[i];
		if(b[i] != t[i])
			flag = 1, ans2++;
		if(b[i] + t[i] == 0)
			emp.insert(i);
		if(t[i])
			color[t[i]].push_back(i);
		else if(b[i])
			color[b[i]].push_back(i);
	}
	if(n==m){
		if(flag)
			printf("-1\n");
		else
			printf("0\n");
		return 0;
	}
	while(1){
		queue<int> q;
		for(int c=1; c<=n; c++){
			if(color[c].size() >= 2){
				if(!t[color[c][0]] || !t[color[c][1]]){
					q.push(c);
				}
			}
		}
		while(!q.empty()){
			int c = q.front();
			q.pop();
			assert(color[c].size() >= 2);
				assert(!t[color[c][0]] || !t[color[c][1]]);
					if(!t[color[c][0]]){
						makemove(color[c][1], color[c][0]);
						done[c] = 1;
						int temp = b[color[c][1]];
						if(temp && !done[temp] && color[temp].size() >= 2){
							q.push(temp);
						}
					}
					else{
						makemove(color[c][0], color[c][1]);
						done[c] = 1;
						int temp = b[color[c][0]];
						if(temp && !done[temp] && color[temp].size() >= 2){
							q.push(temp);
						}
					}
		}
		vector<bool> tch(n+1);
		for(i=1; i<=m; i++){
			if(b[i] && t[i]){
				tch[b[i]] = 1;
				tch[t[i]] = 1;
			}
		}
		for(i=1; i<=n; i++){
			if(!tch[i])
				break;
		}
		if(i==n+1)
			break;
	}
	for(i=1; i<=m; i++){
		if(!t[i])
			solo[b[i]] = 1;
	}
	//simulation
	for(i=m+1; i<=2*m; i++)
		emp.insert(i);
	m *= 2;
	for(i=1; i<=m; i++){
		if(!b[i] || !t[i])
			continue;
		graph[b[i]].push_back(make_pair(i, t[i]));
		graph[t[i]].push_back(make_pair(i, b[i]));
	}
	for(i=1; i<=n; i++){
		assert(graph[i].size());
		if(done[i] || ch[i] || graph[i][0].second == i)
			continue;
		comp.clear();
		cols.clear();
		int emp0 = emp.size();
		needed = emp0;
		//printf("i=%d\n", i);
		dfs(i);
		sort(comp.begin(), comp.end());
		comp.erase(unique(comp.begin(), comp.end()), comp.end());
		deque<int> qa;
		for(int c: cols){
			if(color[c].size() >= 2){
				if(!t[color[c][0]] || !t[color[c][1]])
					qa.push_front(c);
				else
					qa.push_back(c);
			}
		}
		//printf("emp.size=%d\n", emp.size());
		if(qa.empty()){
			int occ = comp[0], e = *emp.begin();
			//printf("occ=%d e=%d\n", occ, e);
			makemove(occ, e);
			for(int c: cols){
				if(color[c].size() >= 2){
					if(!t[color[c][0]] || !t[color[c][1]])
						qa.push_front(c);
					else
						qa.push_back(c);
				}
			}
		}
		//printf("qa.size=%d\n", qa.size());
		while(!qa.empty()){
			//printf("qa.front=%d\n", qa.front());
			if(done[qa.front()]){
				qa.pop_front();
				continue;
			}
			int from = color[qa.front()][0], to = color[qa.front()][1];
			//printf("from=%d to=%d\n", from, to);
			if(t[to])
				swap(from, to);
			if(t[to]){
				if(emp.empty()){
					printf("-1\n");
					return 0;
				}
				int e = *emp.begin();
				//printf("from=%d to=%d e=%d\n", from, to, e);
				makemove(from, e);
				makemove(to, e);
			}
			else{
				makemove(from, to);
			}
			done[qa.front()] = 1;
			qa.pop_front();
			for(int c: {b[from], b[to]}){
				if(c && color[c].size() == 2){
					if(!t[color[c][0]] || !t[color[c][1]])
						qa.push_front(c);
					else
						qa.push_back(c);
				}
			}
		}
		res.push_back(make_pair(emp0 - needed, i));
		assert(emp0 - needed <= 2);
		//printf("i=%d emp0-needed=%d\n", i, emp0-needed);
	}
	sort(res.begin(), res.end(), [](pair<int, int> &u, pair<int, int> &v){return u.first < v.first;});
	m /= 2;
	memset(ch, 0, sizeof(ch));
	for(i=1; i<=n; i++)
		graph[i].clear();
	for(i=1; i<=m; i++){
		b[i]= b0[i];
		t[i] =t0[i];
	}
	emp.clear();
	for(i=1; i<=n; i++)
		color[i].clear();
	ans.clear();
	comp.clear();
	cols.clear();
	memset(done, 0, sizeof(done));
	
	for(i=1; i<=m; i++){
		b[i] = b0[i];
		t[i] = t0[i];
		if(b[i] != t[i])
			flag = 1, ans2++;
		if(b[i] + t[i] == 0)
			emp.insert(i);
		if(t[i])
			color[t[i]].push_back(i);
		else if(b[i])
			color[b[i]].push_back(i);
	}
	if(n==m){
		if(flag)
			printf("-1\n");
		else
			printf("0\n");
		return 0;
	}
	while(1){
		queue<int> q;
		for(int c=1; c<=n; c++){
			if(color[c].size() >= 2){
				if(!t[color[c][0]] || !t[color[c][1]]){
					q.push(c);
				}
			}
		}
		while(!q.empty()){
			int c = q.front();
			q.pop();
			assert(color[c].size() >= 2);
				assert(!t[color[c][0]] || !t[color[c][1]]);
					if(!t[color[c][0]]){
						makemove(color[c][1], color[c][0]);
						done[c] = 1;
						int temp = b[color[c][1]];
						if(temp && !done[temp] && color[temp].size() >= 2){
							q.push(temp);
						}
					}
					else{
						makemove(color[c][0], color[c][1]);
						done[c] = 1;
						int temp = b[color[c][0]];
						if(temp && !done[temp] && color[temp].size() >= 2){
							q.push(temp);
						}
					}
		}
		vector<bool> tch(n+1);
		for(i=1; i<=m; i++){
			if(b[i] && t[i]){
				tch[b[i]] = 1;
				tch[t[i]] = 1;
			}
		}
		for(i=1; i<=n; i++){
			if(!tch[i])
				break;
		}
		if(i==n+1)
			break;
	}
	for(i=1; i<=m; i++){
		if(!t[i])
			solo[b[i]] = 1;
	}
	for(i=1; i<=m; i++){
		if(!b[i] || !t[i])
			continue;
		graph[b[i]].push_back(make_pair(i, t[i]));
		graph[t[i]].push_back(make_pair(i, b[i]));
	}
	for(auto [trash, i]: res){
		//printf("i=%d\n", i);
		assert(graph[i].size());
		if(done[i] || ch[i] || graph[i][0].second == i)
			continue;
		comp.clear();
		cols.clear();
		int emp0 = emp.size();
		needed = emp0;
		//printf("i=%d\n", i);
		dfs(i);
		sort(comp.begin(), comp.end());
		comp.erase(unique(comp.begin(), comp.end()), comp.end());
		deque<int> qa;
		for(int c: cols){
			if(color[c].size() >= 2){
				if(!t[color[c][0]] || !t[color[c][1]])
					qa.push_front(c);
				else
					qa.push_back(c);
			}
		}
		//printf("emp.size=%d\n", emp.size());
		if(qa.empty()){
			int occ = comp[0], e = *emp.begin();
			//printf("occ=%d e=%d\n", occ, e);
			makemove(occ, e);
			for(int c: cols){
				if(color[c].size() >= 2){
					if(!t[color[c][0]] || !t[color[c][1]])
						qa.push_front(c);
					else
						qa.push_back(c);
				}
			}
		}
		//printf("qa.size=%d\n", qa.size());
		while(!qa.empty()){
			//printf("qa.front=%d\n", qa.front());
			if(done[qa.front()]){
				qa.pop_front();
				continue;
			}
			int from = color[qa.front()][0], to = color[qa.front()][1];
			//printf("from=%d to=%d\n", from, to);
			if(t[to])
				swap(from, to);
			if(t[to]){
				if(emp.empty()){
					printf("-1\n");
					return 0;
				}
				int e = *emp.begin();
				//printf("from=%d to=%d e=%d\n", from, to, e);
				makemove(from, e);
				makemove(to, e);
			}
			else{
				makemove(from, to);
			}
			done[qa.front()] = 1;
			qa.pop_front();
			for(int c: {b[from], b[to]}){
				if(c && color[c].size() == 2){
					if(!t[color[c][0]] || !t[color[c][1]])
						qa.push_front(c);
					else
						qa.push_back(c);
				}
			}
		}
		//res.push_back(make_pair(emp0 - needed, i));
	}
	printf("%d\n", ans.size());
	for(auto [u, v]: ans){
		printf("%d %d\n", u, v);
	}
	return 0;
}

Compilation message

Main.cpp: In function 'int main()':
Main.cpp:380:11: warning: format '%d' expects argument of type 'int', but argument 2 has type 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wformat=]
  380 |  printf("%d\n", ans.size());
      |          ~^     ~~~~~~~~~~
      |           |             |
      |           int           std::vector<std::pair<int, int> >::size_type {aka long unsigned int}
      |          %ld
Main.cpp:59:15: warning: unused variable 'j' [-Wunused-variable]
   59 |  int n, m, i, j, ans2 = 0;
      |               ^
Main.cpp:61:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   61 |  scanf("%d %d", &n, &m);
      |  ~~~~~^~~~~~~~~~~~~~~~~
Main.cpp:64:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   64 |   scanf("%d %d", &b[i], &t[i]);
      |   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 32860 KB Output is correct
2 Correct 7 ms 32860 KB Output is correct
3 Correct 6 ms 32860 KB Output is correct
4 Correct 6 ms 32860 KB Output is correct
5 Correct 4 ms 32856 KB Output is correct
6 Correct 5 ms 32348 KB Output is correct
7 Correct 4 ms 32860 KB Output is correct
8 Correct 6 ms 32348 KB Output is correct
9 Correct 5 ms 32348 KB Output is correct
10 Correct 5 ms 32860 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 147 ms 52084 KB Output is correct
2 Correct 189 ms 53144 KB Output is correct
3 Correct 105 ms 51068 KB Output is correct
4 Correct 101 ms 50732 KB Output is correct
5 Correct 157 ms 53272 KB Output is correct

Subtask #3
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 33116 KB Output is correct
2 Correct 5 ms 32608 KB Output is correct
3 Correct 4 ms 32604 KB Output is correct
4 Correct 7 ms 33112 KB Output is correct
5 Correct 6 ms 32344 KB Output is correct
6 Correct 6 ms 33116 KB Output is correct
7 Correct 5 ms 33116 KB Output is correct
8 Correct 5 ms 33116 KB Output is correct
9 Correct 6 ms 33116 KB Output is correct

Subtask #4
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 33116 KB Output is correct
2 Correct 5 ms 32608 KB Output is correct
3 Correct 4 ms 32604 KB Output is correct
4 Correct 7 ms 33112 KB Output is correct
5 Correct 6 ms 32344 KB Output is correct
6 Correct 6 ms 33116 KB Output is correct
7 Correct 5 ms 33116 KB Output is correct
8 Correct 5 ms 33116 KB Output is correct
9 Correct 6 ms 33116 KB Output is correct
10 Correct 282 ms 59728 KB Output is correct
11 Correct 77 ms 38392 KB Output is correct
12 Correct 45 ms 38484 KB Output is correct
13 Correct 288 ms 60224 KB Output is correct
14 Correct 54 ms 37200 KB Output is correct
15 Correct 189 ms 56284 KB Output is correct
16 Correct 264 ms 60160 KB Output is correct
17 Correct 172 ms 56540 KB Output is correct
18 Correct 263 ms 60284 KB Output is correct

Subtask #5
0.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 33116 KB Output is correct
2 Correct 5 ms 33116 KB Output is correct
3 Correct 5 ms 33116 KB Output is correct
4 Correct 6 ms 33116 KB Output is correct
5 Correct 4 ms 32604 KB Output is correct
6 Correct 6 ms 33112 KB Output is correct
7 Correct 5 ms 33116 KB Output is correct
8 Correct 5 ms 33112 KB Output is correct
9 Correct 8 ms 33116 KB Output is correct
10 Correct 5 ms 32604 KB Output is correct
11 Correct 5 ms 33116 KB Output is correct
12 Correct 5 ms 33112 KB Output is correct
13 Correct 5 ms 33116 KB Output is correct
14 Correct 5 ms 32344 KB Output is correct
15 Correct 5 ms 33112 KB Output is correct
16 Correct 5 ms 33116 KB Output is correct
17 Correct 5 ms 33052 KB Output is correct
18 Correct 5 ms 33116 KB Output is correct
19 Correct 5 ms 33112 KB Output is correct
20 Incorrect 5 ms 33112 KB Output isn't correct
21 Halted 0 ms 0 KB -

Subtask #6
0.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 32860 KB Output is correct
2 Correct 7 ms 32860 KB Output is correct
3 Correct 6 ms 32860 KB Output is correct
4 Correct 6 ms 32860 KB Output is correct
5 Correct 4 ms 32856 KB Output is correct
6 Correct 5 ms 32348 KB Output is correct
7 Correct 4 ms 32860 KB Output is correct
8 Correct 6 ms 32348 KB Output is correct
9 Correct 5 ms 32348 KB Output is correct
10 Correct 5 ms 32860 KB Output is correct
11 Correct 147 ms 52084 KB Output is correct
12 Correct 189 ms 53144 KB Output is correct
13 Correct 105 ms 51068 KB Output is correct
14 Correct 101 ms 50732 KB Output is correct
15 Correct 157 ms 53272 KB Output is correct
16 Correct 5 ms 33116 KB Output is correct
17 Correct 5 ms 32608 KB Output is correct
18 Correct 4 ms 32604 KB Output is correct
19 Correct 7 ms 33112 KB Output is correct
20 Correct 6 ms 32344 KB Output is correct
21 Correct 6 ms 33116 KB Output is correct
22 Correct 5 ms 33116 KB Output is correct
23 Correct 5 ms 33116 KB Output is correct
24 Correct 6 ms 33116 KB Output is correct
25 Correct 282 ms 59728 KB Output is correct
26 Correct 77 ms 38392 KB Output is correct
27 Correct 45 ms 38484 KB Output is correct
28 Correct 288 ms 60224 KB Output is correct
29 Correct 54 ms 37200 KB Output is correct
30 Correct 189 ms 56284 KB Output is correct
31 Correct 264 ms 60160 KB Output is correct
32 Correct 172 ms 56540 KB Output is correct
33 Correct 263 ms 60284 KB Output is correct
34 Correct 8 ms 33116 KB Output is correct
35 Correct 5 ms 33116 KB Output is correct
36 Correct 5 ms 33116 KB Output is correct
37 Correct 6 ms 33116 KB Output is correct
38 Correct 4 ms 32604 KB Output is correct
39 Correct 6 ms 33112 KB Output is correct
40 Correct 5 ms 33116 KB Output is correct
41 Correct 5 ms 33112 KB Output is correct
42 Correct 8 ms 33116 KB Output is correct
43 Correct 5 ms 32604 KB Output is correct
44 Correct 5 ms 33116 KB Output is correct
45 Correct 5 ms 33112 KB Output is correct
46 Correct 5 ms 33116 KB Output is correct
47 Correct 5 ms 32344 KB Output is correct
48 Correct 5 ms 33112 KB Output is correct
49 Correct 5 ms 33116 KB Output is correct
50 Correct 5 ms 33052 KB Output is correct
51 Correct 5 ms 33116 KB Output is correct
52 Correct 5 ms 33112 KB Output is correct
53 Incorrect 5 ms 33112 KB Output isn't correct
54 Halted 0 ms 0 KB -