답안 #981207

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
981207 2024-05-13T02:19:57 Z Lib 자매 도시 (APIO20_swap) C++14
7 / 100
330 ms 66744 KB
#include <bits/stdc++.h>
using namespace std;
int n,m;
vector <vector <int> > InComponents;
vector <vector <int> > adj; //the edge list of the KRT
vector <int> TVector;
int RootID; //ID of the root node of the KRT;
struct Edge{
	long long Weight;
	int Start;
	int End;
};
bool operator< (const Edge &x, const Edge &y){
	return x.Weight<y.Weight;
}
Edge Elist[500003];
int Depth[500003];
int Deg[500003];
int CurRep[500003]; //id of the respresentative node on the KRT
int Par[500003]; //Parent of node with id i on the KRT;
int Toggle[500003]; //is the i-th node on the KRT toggled?
int Check[500003];
int Ancestor[500003][20];
long long Val[500003];//the value of the i-th node of the KRT
vector <int> KRTID;
void DSU(int id, int u, int v, int w){
	Deg[u]++;
	Deg[v]++;
	//u and v belongs to the same component. The component now has a cycle. Immediately toggle the root node of the current 
	//subtree that includes both u and v on the KRT
	if(CurRep[u]==CurRep[v]){
		//The node isn't toggled just yet. Toggle it immediately
		if(!Toggle[CurRep[u]]){
			Toggle[CurRep[u]]=1;
			Val[CurRep[u]]=w;
		}else{
		//The node is already toggled by an edge with lower edge. Only a fucking dumbass would touch it - already minimized
		//toggle value. Just leave it alone
		}
	}else{
		//u and v doesn't belong to the same component. Merge them
		int CurID=n-1+id;
		int OldComp1=CurRep[u], OldComp2=CurRep[v];
		adj[CurRep[u]].push_back(CurID);
		adj[CurRep[v]].push_back(CurID);
		adj[CurID].push_back(CurRep[u]);
		adj[CurID].push_back(CurRep[v]);
		Par[CurRep[u]]=CurID;
		Par[CurRep[v]]=CurID;
		if(InComponents[u].size()>InComponents[v].size()){
			swap(u,v);
			//Small to large merging
		}
		for(int i=0;i<InComponents[u].size();i++){
			InComponents[CurID].push_back(InComponents[u][i]);
			CurRep[InComponents[u][i]]=CurID;
		}
		for(int i=0;i<InComponents[v].size();i++){
			InComponents[CurID].push_back(InComponents[v][i]);
			CurRep[InComponents[v][i]]=CurID;
		}
		Val[CurID]=w;
		//if either of the components are toggled already (having a cycle OR a vertex with degree >3)
		//OR the merged component has a vertex with degree >3 (either u or v), toggle immediately
		if(Toggle[OldComp1]||Toggle[OldComp2]||Deg[u]>2||Deg[v]>2){
			Toggle[CurID]=1;
		}
		KRTID.push_back(CurID);
		RootID=CurID;
	}
}
void init(int N, int M, vector <int> U, vector <int> V, vector <int> W){
	n=N;
	m=M;
	for(int i=0;i<n+m+5;i++){
		InComponents.push_back(TVector);
		adj.push_back(TVector);
	}
	for(int i=1;i<=m;i++){
		Elist[i].Weight=W[i-1];
		Elist[i].Start=U[i-1];
		Elist[i].End=V[i-1];
	}
	sort(Elist+1,Elist+m+1);
	for(int i=0;i<n;i++){
		CurRep[i]=i;
		InComponents[i].push_back(i);
		KRTID.push_back(i);
	}
	for(int i=1;i<=m;i++){
		DSU(i,Elist[i].Start,Elist[i].End,Elist[i].Weight);
	}
	//The KRT is now built. BFS from the root node and initialize LCA or something
	deque <int> dq;
	dq.push_back(RootID);
	Check[RootID]=1;
	int Cur;
	while(!dq.empty()){
		Cur=dq.front();
		for(int i=0;i<adj[Cur].size();i++){
			if(!Check[adj[Cur][i]]){
				dq.push_back(adj[Cur][i]);
				Check[adj[Cur][i]]=1;
				Depth[adj[Cur][i]]=Depth[Cur]+1;
			}
		}
		dq.pop_front();
	}
	Par[RootID]=500000;
	Par[500000]=500000;
	Toggle[500000]=1;
	for(int i=0;i<=19;i++){
		for(int k=0;k<KRTID.size();k++){
			if(i==0){
				Ancestor[KRTID[k]][i]=Par[KRTID[k]];
			}else{
				Ancestor[KRTID[k]][i]=Ancestor[Ancestor[KRTID[k]][i-1]][i-1];
			}
		}
	}
}

int getMinimumFuelCapacity(int x, int y){
	//I thought that we actually need to use binary lifting to find LCA and then jump from the LCA to find the nearest
	//toggled node on the KRT
	//But apparently small-to-large merging ensures that the depth of the tree is always logN or something, so bruteforcing
	//it is
	//ok nvm this guy is a fucking moron lmao LogN depth my ass. Wrong analysis, wasted 5 minutes. Fuck me
	if(Depth[x]<Depth[y]){
		swap(x,y);
	}
	int JumpLevel=Depth[x]-Depth[y];
	for(int i=19;i>=0;i--){
		if(JumpLevel >> i & 1){
			x=Ancestor[x][i];
		}
	}
	for(int i=19;i>=0;i--){
		if(Ancestor[x][i]!=Ancestor[y][i]){
			x=Ancestor[x][i];
			y=Ancestor[y][i];
		}
	}
	x=Par[x];
	SkipPoint:;
	if(Toggle[x]){
		return Val[x];
	}
	
	for(int i=19;i>=0;i--){
		if(!Toggle[Ancestor[x][i]]){
			x=Ancestor[x][i];
		}
	}
	x=Par[x];
	if(Toggle[x]&&x!=500000){
		return Val[x];
	}
	return -1;
}

Compilation message

swap.cpp: In function 'void DSU(int, int, int, int)':
swap.cpp:54:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   54 |   for(int i=0;i<InComponents[u].size();i++){
      |               ~^~~~~~~~~~~~~~~~~~~~~~~
swap.cpp:58:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   58 |   for(int i=0;i<InComponents[v].size();i++){
      |               ~^~~~~~~~~~~~~~~~~~~~~~~
swap.cpp: In function 'void init(int, int, std::vector<int>, std::vector<int>, std::vector<int>)':
swap.cpp:100:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  100 |   for(int i=0;i<adj[Cur].size();i++){
      |               ~^~~~~~~~~~~~~~~~
swap.cpp:113:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  113 |   for(int k=0;k<KRTID.size();k++){
      |               ~^~~~~~~~~~~~~
swap.cpp: In function 'int getMinimumFuelCapacity(int, int)':
swap.cpp:145:2: warning: label 'SkipPoint' defined but not used [-Wunused-label]
  145 |  SkipPoint:;
      |  ^~~~~~~~~
# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 12636 KB Output is correct
2 Correct 3 ms 12636 KB Output is correct
3 Correct 2 ms 12636 KB Output is correct
4 Correct 2 ms 12892 KB Output is correct
5 Correct 3 ms 12892 KB Output is correct
6 Correct 2 ms 12892 KB Output is correct
7 Correct 2 ms 12892 KB Output is correct
8 Correct 3 ms 12892 KB Output is correct
9 Correct 101 ms 52196 KB Output is correct
10 Correct 125 ms 62140 KB Output is correct
11 Correct 145 ms 62020 KB Output is correct
12 Correct 135 ms 61468 KB Output is correct
13 Correct 122 ms 60956 KB Output is correct
14 Correct 124 ms 50544 KB Output is correct
15 Correct 223 ms 65412 KB Output is correct
16 Correct 216 ms 60488 KB Output is correct
17 Correct 226 ms 63356 KB Output is correct
18 Correct 330 ms 63720 KB Output is correct
19 Incorrect 86 ms 26684 KB Output isn't correct
20 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 12636 KB Output is correct
2 Correct 3 ms 12636 KB Output is correct
3 Correct 215 ms 63440 KB Output is correct
4 Correct 211 ms 64712 KB Output is correct
5 Correct 192 ms 66744 KB Output is correct
6 Correct 190 ms 65960 KB Output is correct
7 Correct 207 ms 63864 KB Output is correct
8 Correct 237 ms 63568 KB Output is correct
9 Correct 193 ms 66720 KB Output is correct
10 Correct 190 ms 63580 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 12636 KB Output is correct
2 Correct 3 ms 12636 KB Output is correct
3 Correct 2 ms 12636 KB Output is correct
4 Correct 2 ms 12892 KB Output is correct
5 Correct 3 ms 12892 KB Output is correct
6 Correct 2 ms 12892 KB Output is correct
7 Correct 2 ms 12892 KB Output is correct
8 Correct 3 ms 12892 KB Output is correct
9 Incorrect 2 ms 12636 KB Output isn't correct
10 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Incorrect 2 ms 12636 KB Output isn't correct
2 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 12636 KB Output is correct
2 Correct 3 ms 12636 KB Output is correct
3 Correct 2 ms 12636 KB Output is correct
4 Correct 2 ms 12892 KB Output is correct
5 Correct 3 ms 12892 KB Output is correct
6 Correct 2 ms 12892 KB Output is correct
7 Correct 2 ms 12892 KB Output is correct
8 Correct 3 ms 12892 KB Output is correct
9 Correct 101 ms 52196 KB Output is correct
10 Correct 125 ms 62140 KB Output is correct
11 Correct 145 ms 62020 KB Output is correct
12 Correct 135 ms 61468 KB Output is correct
13 Correct 122 ms 60956 KB Output is correct
14 Correct 124 ms 50544 KB Output is correct
15 Correct 223 ms 65412 KB Output is correct
16 Correct 216 ms 60488 KB Output is correct
17 Correct 226 ms 63356 KB Output is correct
18 Correct 330 ms 63720 KB Output is correct
19 Correct 215 ms 63440 KB Output is correct
20 Correct 211 ms 64712 KB Output is correct
21 Correct 192 ms 66744 KB Output is correct
22 Correct 190 ms 65960 KB Output is correct
23 Correct 207 ms 63864 KB Output is correct
24 Correct 237 ms 63568 KB Output is correct
25 Correct 193 ms 66720 KB Output is correct
26 Correct 190 ms 63580 KB Output is correct
27 Incorrect 3 ms 12892 KB Output isn't correct
28 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Incorrect 2 ms 12636 KB Output isn't correct
2 Halted 0 ms 0 KB -