oj.uz

Submission #704592

# Submission time Handle Problem Language Result Execution time Memory
704592 2023-03-02T11:23:18 Z amirhoseinfar1385 Mousetrap (CEOI17_mousetrap) C++17
65 / 100
 906 ms 217284 KB 
#include<bits/stdc++.h>
using namespace std;
const int maxn=1000000+5;
vector<int>adj[maxn],alldp[maxn];
int par[maxn],vis[maxn],n,t,m,dp[maxn],ted[maxn],mainres;
priority_queue<pair<int,int>>pq;
int val[maxn];

void dfs(int u,int para=0){
	par[u]=para;
	for(int x:adj[u])
	{
		if(x!=para){
			dfs(x,u);
			vis[u]|=vis[x];
			if(vis[x]==0){
				ted[u]++;
				alldp[u].push_back(dp[x]);
			}	
		}
	}
	if((int)alldp[u].size()>0){
		if((int)alldp[u].size()==1){
			dp[u]=2;
		}
		else{
			sort(alldp[u].begin(),alldp[u].end());
			int maxa1=alldp[u].back(),maxa2=alldp[u][(int)alldp[u].size()-2];
			dp[u]=maxa2+ted[u]-1;
			dp[u]++;
		}
	}	
	else{
		dp[u]=1;
	}
}

void solve(int had){
	int allted=0,now=had;
	while(now!=t){
		//cout<<"1 "<<now<<endl;
		allted+=ted[now];
		now=par[now];
	}
	int fted=allted;
	now=had;
	int unnow=1;
	while(now!=t){
		int ffted=allted;
		for(int i=(int)alldp[now].size()-1;i>=0;i--){
			int x=alldp[now][i]+allted-1+(int)pq.size();
			if((int)pq.size()<unnow){
				pq.push(make_pair(-x,now));
				val[now]++;
				allted--;
			}
			else{
				pair<int,int> y=pq.top();
				if(-y.first<=x){
					pq.pop();
					pq.push(make_pair(-x,now));
					val[y.second]--;
					val[now]++;
					allted--;
					if(y.second==now){
						allted++;
					}
				}
			}
		}
		allted=ffted-ted[now];
		now=par[now];
		unnow++;
	}
	allted=fted;
	int resa=(int)pq.size();
	now=had;
	int fn=0;
	while(now!=t){
		for(int i=0;i<(int)alldp[now].size()-(val[now]-fn);i++){
			int x=alldp[now][i]+allted-1;
		//	cout<<now<<" asd "<<x<<"\n";
			resa=max(resa,x+fn);
		}
		allted-=ted[now];
		fn=val[now];
		val[par[now]]+=val[now];
		now=par[now];
	}
	mainres=resa;
}

int main(){
	ios::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	cin>>n>>t>>m;
	for(int i=0;i<n-1;i++){
		int u,v;
		cin>>u>>v;
		adj[u].push_back(v);
		adj[v].push_back(u);
	}
	vis[m]=1;
	dfs(t);
	solve(m);
	cout<<mainres<<"\n";
}

Compilation message

mousetrap.cpp: In function 'void dfs(int, int)':
mousetrap.cpp:28:8: warning: unused variable 'maxa1' [-Wunused-variable]
   28 |    int maxa1=alldp[u].back(),maxa2=alldp[u][(int)alldp[u].size()-2];
      |        ^~~~~

Subtask #1
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 24 ms 47316 KB Output is correct
2 Correct 24 ms 47264 KB Output is correct
3 Correct 25 ms 47208 KB Output is correct
4 Correct 23 ms 47316 KB Output is correct
5 Correct 24 ms 47312 KB Output is correct
6 Correct 25 ms 47216 KB Output is correct
7 Correct 25 ms 47304 KB Output is correct
8 Correct 24 ms 47300 KB Output is correct
9 Correct 27 ms 47260 KB Output is correct
10 Correct 24 ms 47284 KB Output is correct

Subtask #2
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 321 ms 106040 KB Output is correct
2 Correct 302 ms 112128 KB Output is correct
3 Correct 861 ms 124612 KB Output is correct
4 Correct 422 ms 85864 KB Output is correct
5 Correct 847 ms 124656 KB Output is correct
6 Correct 863 ms 124732 KB Output is correct

Subtask #3
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 24 ms 47316 KB Output is correct
2 Correct 24 ms 47264 KB Output is correct
3 Correct 25 ms 47208 KB Output is correct
4 Correct 23 ms 47316 KB Output is correct
5 Correct 24 ms 47312 KB Output is correct
6 Correct 25 ms 47216 KB Output is correct
7 Correct 25 ms 47304 KB Output is correct
8 Correct 24 ms 47300 KB Output is correct
9 Correct 27 ms 47260 KB Output is correct
10 Correct 24 ms 47284 KB Output is correct
11 Correct 29 ms 47320 KB Output is correct
12 Correct 25 ms 47332 KB Output is correct
13 Correct 25 ms 47316 KB Output is correct
14 Correct 28 ms 47404 KB Output is correct
15 Correct 25 ms 47444 KB Output is correct
16 Correct 25 ms 47392 KB Output is correct
17 Correct 24 ms 47392 KB Output is correct
18 Correct 23 ms 47316 KB Output is correct
19 Correct 24 ms 47308 KB Output is correct
20 Correct 24 ms 47412 KB Output is correct
21 Correct 23 ms 47388 KB Output is correct
22 Correct 29 ms 47308 KB Output is correct

Subtask #4
0 / 35.0

# Verdict Execution time Memory Grader output
1 Correct 24 ms 47316 KB Output is correct
2 Correct 24 ms 47264 KB Output is correct
3 Correct 25 ms 47208 KB Output is correct
4 Correct 23 ms 47316 KB Output is correct
5 Correct 24 ms 47312 KB Output is correct
6 Correct 25 ms 47216 KB Output is correct
7 Correct 25 ms 47304 KB Output is correct
8 Correct 24 ms 47300 KB Output is correct
9 Correct 27 ms 47260 KB Output is correct
10 Correct 24 ms 47284 KB Output is correct
11 Correct 321 ms 106040 KB Output is correct
12 Correct 302 ms 112128 KB Output is correct
13 Correct 861 ms 124612 KB Output is correct
14 Correct 422 ms 85864 KB Output is correct
15 Correct 847 ms 124656 KB Output is correct
16 Correct 863 ms 124732 KB Output is correct
17 Correct 29 ms 47320 KB Output is correct
18 Correct 25 ms 47332 KB Output is correct
19 Correct 25 ms 47316 KB Output is correct
20 Correct 28 ms 47404 KB Output is correct
21 Correct 25 ms 47444 KB Output is correct
22 Correct 25 ms 47392 KB Output is correct
23 Correct 24 ms 47392 KB Output is correct
24 Correct 23 ms 47316 KB Output is correct
25 Correct 24 ms 47308 KB Output is correct
26 Correct 24 ms 47412 KB Output is correct
27 Correct 23 ms 47388 KB Output is correct
28 Correct 29 ms 47308 KB Output is correct
29 Correct 24 ms 47312 KB Output is correct
30 Correct 336 ms 119352 KB Output is correct
31 Correct 354 ms 119392 KB Output is correct
32 Correct 332 ms 185964 KB Output is correct
33 Correct 404 ms 217284 KB Output is correct
34 Correct 864 ms 124648 KB Output is correct
35 Incorrect 906 ms 124868 KB Output isn't correct
36 Halted 0 ms 0 KB -