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Submission #1044356

# Submission time Handle Problem Language Result Execution time Memory
1044356 2024-08-05T09:02:19 Z 김은성(#11005) Parking (CEOI22_parking) C++17
60 / 100
 209 ms 60288 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();
	res.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(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));
	}
	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 5 ms 32860 KB Output is correct
2 Correct 4 ms 32812 KB Output is correct
3 Correct 5 ms 32860 KB Output is correct
4 Correct 5 ms 32860 KB Output is correct
5 Correct 5 ms 32860 KB Output is correct
6 Correct 4 ms 32348 KB Output is correct
7 Correct 5 ms 33068 KB Output is correct
8 Correct 4 ms 32348 KB Output is correct
9 Correct 4 ms 32344 KB Output is correct
10 Correct 5 ms 32856 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 120 ms 52144 KB Output is correct
2 Correct 140 ms 53108 KB Output is correct
3 Correct 88 ms 51068 KB Output is correct
4 Correct 86 ms 50804 KB Output is correct
5 Correct 122 ms 53360 KB Output is correct

Subtask #3
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 33112 KB Output is correct
2 Correct 5 ms 32600 KB Output is correct
3 Correct 5 ms 32348 KB Output is correct
4 Correct 5 ms 33112 KB Output is correct
5 Correct 4 ms 32348 KB Output is correct
6 Correct 6 ms 33112 KB Output is correct
7 Correct 5 ms 33112 KB Output is correct
8 Correct 5 ms 33116 KB Output is correct
9 Correct 6 ms 33112 KB Output is correct

Subtask #4
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 33112 KB Output is correct
2 Correct 5 ms 32600 KB Output is correct
3 Correct 5 ms 32348 KB Output is correct
4 Correct 5 ms 33112 KB Output is correct
5 Correct 4 ms 32348 KB Output is correct
6 Correct 6 ms 33112 KB Output is correct
7 Correct 5 ms 33112 KB Output is correct
8 Correct 5 ms 33116 KB Output is correct
9 Correct 6 ms 33112 KB Output is correct
10 Correct 194 ms 59728 KB Output is correct
11 Correct 38 ms 38480 KB Output is correct
12 Correct 41 ms 38492 KB Output is correct
13 Correct 185 ms 60280 KB Output is correct
14 Correct 42 ms 37200 KB Output is correct
15 Correct 122 ms 56160 KB Output is correct
16 Correct 206 ms 60028 KB Output is correct
17 Correct 137 ms 56516 KB Output is correct
18 Correct 209 ms 60288 KB Output is correct

Subtask #5
0.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 33116 KB Output is correct
2 Correct 6 ms 33112 KB Output is correct
3 Correct 5 ms 33116 KB Output is correct
4 Correct 5 ms 33064 KB Output is correct
5 Correct 4 ms 32604 KB Output is correct
6 Correct 5 ms 33112 KB Output is correct
7 Correct 5 ms 33116 KB Output is correct
8 Incorrect 5 ms 33116 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 5 ms 32860 KB Output is correct
2 Correct 4 ms 32812 KB Output is correct
3 Correct 5 ms 32860 KB Output is correct
4 Correct 5 ms 32860 KB Output is correct
5 Correct 5 ms 32860 KB Output is correct
6 Correct 4 ms 32348 KB Output is correct
7 Correct 5 ms 33068 KB Output is correct
8 Correct 4 ms 32348 KB Output is correct
9 Correct 4 ms 32344 KB Output is correct
10 Correct 5 ms 32856 KB Output is correct
11 Correct 120 ms 52144 KB Output is correct
12 Correct 140 ms 53108 KB Output is correct
13 Correct 88 ms 51068 KB Output is correct
14 Correct 86 ms 50804 KB Output is correct
15 Correct 122 ms 53360 KB Output is correct
16 Correct 5 ms 33112 KB Output is correct
17 Correct 5 ms 32600 KB Output is correct
18 Correct 5 ms 32348 KB Output is correct
19 Correct 5 ms 33112 KB Output is correct
20 Correct 4 ms 32348 KB Output is correct
21 Correct 6 ms 33112 KB Output is correct
22 Correct 5 ms 33112 KB Output is correct
23 Correct 5 ms 33116 KB Output is correct
24 Correct 6 ms 33112 KB Output is correct
25 Correct 194 ms 59728 KB Output is correct
26 Correct 38 ms 38480 KB Output is correct
27 Correct 41 ms 38492 KB Output is correct
28 Correct 185 ms 60280 KB Output is correct
29 Correct 42 ms 37200 KB Output is correct
30 Correct 122 ms 56160 KB Output is correct
31 Correct 206 ms 60028 KB Output is correct
32 Correct 137 ms 56516 KB Output is correct
33 Correct 209 ms 60288 KB Output is correct
34 Correct 5 ms 33116 KB Output is correct
35 Correct 6 ms 33112 KB Output is correct
36 Correct 5 ms 33116 KB Output is correct
37 Correct 5 ms 33064 KB Output is correct
38 Correct 4 ms 32604 KB Output is correct
39 Correct 5 ms 33112 KB Output is correct
40 Correct 5 ms 33116 KB Output is correct
41 Incorrect 5 ms 33116 KB Output isn't correct
42 Halted 0 ms 0 KB -