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Submission #1044367

# Submission time Handle Problem Language Result Execution time Memory
1044367 2024-08-05T09:04:26 Z 김은성(#11005) Parking (CEOI22_parking) C++17
60 / 100
 241 ms 60180 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));
	}
	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:378:11: 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=]
  378 |  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 7 ms 32856 KB Output is correct
2 Correct 6 ms 32856 KB Output is correct
3 Correct 4 ms 32856 KB Output is correct
4 Correct 5 ms 32860 KB Output is correct
5 Correct 5 ms 32860 KB Output is correct
6 Correct 5 ms 32348 KB Output is correct
7 Correct 5 ms 32856 KB Output is correct
8 Correct 6 ms 32348 KB Output is correct
9 Correct 7 ms 32348 KB Output is correct
10 Correct 6 ms 32860 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 110 ms 52224 KB Output is correct
2 Correct 152 ms 53252 KB Output is correct
3 Correct 103 ms 51088 KB Output is correct
4 Correct 87 ms 50820 KB Output is correct
5 Correct 143 ms 53480 KB Output is correct

Subtask #3
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 33116 KB Output is correct
2 Correct 5 ms 32604 KB Output is correct
3 Correct 8 ms 32344 KB Output is correct
4 Correct 6 ms 33116 KB Output is correct
5 Correct 7 ms 32348 KB Output is correct
6 Correct 6 ms 33112 KB Output is correct
7 Correct 6 ms 33140 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 6 ms 33116 KB Output is correct
2 Correct 5 ms 32604 KB Output is correct
3 Correct 8 ms 32344 KB Output is correct
4 Correct 6 ms 33116 KB Output is correct
5 Correct 7 ms 32348 KB Output is correct
6 Correct 6 ms 33112 KB Output is correct
7 Correct 6 ms 33140 KB Output is correct
8 Correct 5 ms 33116 KB Output is correct
9 Correct 6 ms 33116 KB Output is correct
10 Correct 241 ms 59748 KB Output is correct
11 Correct 45 ms 38520 KB Output is correct
12 Correct 53 ms 38428 KB Output is correct
13 Correct 219 ms 60168 KB Output is correct
14 Correct 55 ms 37212 KB Output is correct
15 Correct 170 ms 56284 KB Output is correct
16 Correct 222 ms 60032 KB Output is correct
17 Correct 200 ms 56532 KB Output is correct
18 Correct 239 ms 60180 KB Output is correct

Subtask #5
0.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 33112 KB Output is correct
2 Correct 6 ms 33088 KB Output is correct
3 Correct 5 ms 33116 KB Output is correct
4 Correct 6 ms 33116 KB Output is correct
5 Correct 5 ms 32600 KB Output is correct
6 Correct 5 ms 33116 KB Output is correct
7 Correct 6 ms 33116 KB Output is correct
8 Incorrect 5 ms 33112 KB Output isn't correct
9 Halted 0 ms 0 KB -

Subtask #6
0.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 7 ms 32856 KB Output is correct
2 Correct 6 ms 32856 KB Output is correct
3 Correct 4 ms 32856 KB Output is correct
4 Correct 5 ms 32860 KB Output is correct
5 Correct 5 ms 32860 KB Output is correct
6 Correct 5 ms 32348 KB Output is correct
7 Correct 5 ms 32856 KB Output is correct
8 Correct 6 ms 32348 KB Output is correct
9 Correct 7 ms 32348 KB Output is correct
10 Correct 6 ms 32860 KB Output is correct
11 Correct 110 ms 52224 KB Output is correct
12 Correct 152 ms 53252 KB Output is correct
13 Correct 103 ms 51088 KB Output is correct
14 Correct 87 ms 50820 KB Output is correct
15 Correct 143 ms 53480 KB Output is correct
16 Correct 6 ms 33116 KB Output is correct
17 Correct 5 ms 32604 KB Output is correct
18 Correct 8 ms 32344 KB Output is correct
19 Correct 6 ms 33116 KB Output is correct
20 Correct 7 ms 32348 KB Output is correct
21 Correct 6 ms 33112 KB Output is correct
22 Correct 6 ms 33140 KB Output is correct
23 Correct 5 ms 33116 KB Output is correct
24 Correct 6 ms 33116 KB Output is correct
25 Correct 241 ms 59748 KB Output is correct
26 Correct 45 ms 38520 KB Output is correct
27 Correct 53 ms 38428 KB Output is correct
28 Correct 219 ms 60168 KB Output is correct
29 Correct 55 ms 37212 KB Output is correct
30 Correct 170 ms 56284 KB Output is correct
31 Correct 222 ms 60032 KB Output is correct
32 Correct 200 ms 56532 KB Output is correct
33 Correct 239 ms 60180 KB Output is correct
34 Correct 5 ms 33112 KB Output is correct
35 Correct 6 ms 33088 KB Output is correct
36 Correct 5 ms 33116 KB Output is correct
37 Correct 6 ms 33116 KB Output is correct
38 Correct 5 ms 32600 KB Output is correct
39 Correct 5 ms 33116 KB Output is correct
40 Correct 6 ms 33116 KB Output is correct
41 Incorrect 5 ms 33112 KB Output isn't correct
42 Halted 0 ms 0 KB -