oj.uz

Submission #1044246

# Submission time Handle Problem Language Result Execution time Memory
1044246 2024-08-05T08:18:40 Z 김은성(#11005) Parking (CEOI22_parking) C++17
50 / 100
 153 ms 42692 KB 
#include <bits/stdc++.h>
using namespace std;
bool ch[200009];
vector<pair<int, int> > graph[200009];
int b[200009], t[200009];
unordered_set<int> emp;
vector<int> color[200009];
vector<pair<int, int> > ans;
vector<int> comp, cols;
bool done[200009];
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);
	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];
			t[occ] = 0;
			emp.erase(e);
			color[b[e]].push_back(e);
		}
	}
}
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]);
		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;
	}
	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();
		if(color[c].size() >= 2){
			if(!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);
					}
				}
			}
		}
	}
	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++){
		if(ch[i] || graph[i][0].second == i)
			continue;
		comp.clear();
		cols.clear();
		//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);
				}
			}
		}
	}
	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:182:11: 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=]
  182 |  printf("%d\n", ans.size());
      |          ~^     ~~~~~~~~~~
      |           |             |
      |           int           std::vector<std::pair<int, int> >::size_type {aka long unsigned int}
      |          %ld
Main.cpp:54:15: warning: unused variable 'j' [-Wunused-variable]
   54 |  int n, m, i, j, ans2 = 0;
      |               ^
Main.cpp:56:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   56 |  scanf("%d %d", &n, &m);
      |  ~~~~~^~~~~~~~~~~~~~~~~
Main.cpp:59:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   59 |   scanf("%d %d", &b[i], &t[i]);
      |   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 11352 KB Output is correct
2 Correct 2 ms 11356 KB Output is correct
3 Correct 2 ms 11356 KB Output is correct
4 Correct 2 ms 11356 KB Output is correct
5 Correct 2 ms 11352 KB Output is correct
6 Correct 2 ms 11356 KB Output is correct
7 Correct 2 ms 11356 KB Output is correct
8 Correct 2 ms 11356 KB Output is correct
9 Correct 2 ms 11352 KB Output is correct
10 Correct 2 ms 11356 KB Output is correct

Subtask #2
0.0 / 10.0

# Verdict Execution time Memory Grader output
1 Runtime error 61 ms 42692 KB Execution killed with signal 11
2 Halted 0 ms 0 KB -

Subtask #3
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 11352 KB Output is correct
2 Correct 2 ms 11356 KB Output is correct
3 Correct 2 ms 11352 KB Output is correct
4 Correct 2 ms 11356 KB Output is correct
5 Correct 2 ms 11356 KB Output is correct
6 Correct 2 ms 11356 KB Output is correct
7 Correct 2 ms 11352 KB Output is correct
8 Correct 2 ms 11352 KB Output is correct
9 Correct 3 ms 11356 KB Output is correct

Subtask #4
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 11352 KB Output is correct
2 Correct 2 ms 11356 KB Output is correct
3 Correct 2 ms 11352 KB Output is correct
4 Correct 2 ms 11356 KB Output is correct
5 Correct 2 ms 11356 KB Output is correct
6 Correct 2 ms 11356 KB Output is correct
7 Correct 2 ms 11352 KB Output is correct
8 Correct 2 ms 11352 KB Output is correct
9 Correct 3 ms 11356 KB Output is correct
10 Correct 153 ms 29192 KB Output is correct
11 Correct 37 ms 17496 KB Output is correct
12 Correct 42 ms 17232 KB Output is correct
13 Correct 133 ms 28176 KB Output is correct
14 Correct 36 ms 16016 KB Output is correct
15 Correct 52 ms 22096 KB Output is correct
16 Correct 130 ms 29428 KB Output is correct
17 Correct 53 ms 22612 KB Output is correct
18 Correct 121 ms 28864 KB Output is correct

Subtask #5
0.0 / 25.0

# Verdict Execution time Memory Grader output
1 Runtime error 10 ms 22876 KB Execution killed with signal 11
2 Halted 0 ms 0 KB -

Subtask #6
0.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 11352 KB Output is correct
2 Correct 2 ms 11356 KB Output is correct
3 Correct 2 ms 11356 KB Output is correct
4 Correct 2 ms 11356 KB Output is correct
5 Correct 2 ms 11352 KB Output is correct
6 Correct 2 ms 11356 KB Output is correct
7 Correct 2 ms 11356 KB Output is correct
8 Correct 2 ms 11356 KB Output is correct
9 Correct 2 ms 11352 KB Output is correct
10 Correct 2 ms 11356 KB Output is correct
11 Runtime error 61 ms 42692 KB Execution killed with signal 11
12 Halted 0 ms 0 KB -