oj.uz

Submission #982069

# Submission time Handle Problem Language Result Execution time Memory
982069 2024-05-13T18:48:15 Z Lib Swapping Cities (APIO20_swap) C++14
7 / 100
 256 ms 64168 KB 
#include <bits/stdc++.h>
using namespace std;
int n,m,a,b,c;
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;
int GetRep(int u){
	if(CurRep[u]==u){
		return u;
	}else{
		return CurRep[u]=GetRep(CurRep[u]);
	}
}
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
	int RepU=GetRep(u), RepV=GetRep(v);
	if(RepU==RepV){
		//The node isn't toggled just yet. Toggle it immediately
		if(!Toggle[RepU]){
			Toggle[RepU]=1;
			Val[RepU]=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=RepU, OldComp2=RepV;
		adj[RepU].push_back(CurID);
		adj[RepV].push_back(CurID);
		adj[CurID].push_back(RepU);
		adj[CurID].push_back(RepV);
		Par[RepU]=CurID;
		Par[RepV]=CurID;
		CurRep[RepU]=CurID;
		CurRep[RepV]=CurID;
		Val[CurID]=w; //if I got WA because I forgot to set the fucking node weight to the nodes on the KRT, I'll shove 3 fingers up my ass.
		//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<=m+n+1;i++){
		CurRep[i]=i;
	}		
	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();
		//cout<<Cur<<" ";
		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];
	y=Par[y];
	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;
}
/*
int main(){
	cin>>n>>m;
	vector <int> U,V,W;
	for(int i=1;i<=m;i++){
		cin>>a>>b>>c;
		U.push_back(a);
		V.push_back(b);
		W.push_back(c);
	}
	init(n,m,U,V,W);
}
*/
/*
5 6
0 1 4
0 2 4
1 2 1
1 3 2
1 4 10
2 3 3
*/

Compilation message

swap.cpp: In function 'void init(int, int, std::vector<int>, std::vector<int>, std::vector<int>)':
swap.cpp:102:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  102 |   for(int i=0;i<adj[Cur].size();i++){
      |               ~^~~~~~~~~~~~~~~~
swap.cpp:115:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  115 |   for(int k=0;k<KRTID.size();k++){
      |               ~^~~~~~~~~~~~~
swap.cpp: In function 'int getMinimumFuelCapacity(int, int)':
swap.cpp:147:2: warning: label 'SkipPoint' defined but not used [-Wunused-label]
  147 |  SkipPoint:;
      |  ^~~~~~~~~

Subtask #1
0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 12636 KB Output is correct
2 Correct 2 ms 12636 KB Output is correct
3 Correct 2 ms 12636 KB Output is correct
4 Correct 2 ms 12636 KB Output is correct
5 Correct 2 ms 12980 KB Output is correct
6 Correct 2 ms 12892 KB Output is correct
7 Correct 3 ms 12888 KB Output is correct
8 Correct 2 ms 12892 KB Output is correct
9 Correct 82 ms 47580 KB Output is correct
10 Correct 95 ms 56532 KB Output is correct
11 Correct 96 ms 57304 KB Output is correct
12 Correct 103 ms 56348 KB Output is correct
13 Correct 91 ms 57540 KB Output is correct
14 Correct 80 ms 47904 KB Output is correct
15 Correct 206 ms 57260 KB Output is correct
16 Correct 177 ms 56012 KB Output is correct
17 Correct 215 ms 60296 KB Output is correct
18 Correct 256 ms 60976 KB Output is correct
19 Incorrect 81 ms 25408 KB Output isn't correct
20 Halted 0 ms 0 KB -

Subtask #2
7.0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 12636 KB Output is correct
2 Correct 2 ms 12636 KB Output is correct
3 Correct 217 ms 59268 KB Output is correct
4 Correct 195 ms 64120 KB Output is correct
5 Correct 176 ms 63360 KB Output is correct
6 Correct 220 ms 63488 KB Output is correct
7 Correct 170 ms 62620 KB Output is correct
8 Correct 170 ms 59340 KB Output is correct
9 Correct 173 ms 64168 KB Output is correct
10 Correct 170 ms 62644 KB Output is correct

Subtask #3
0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 12636 KB Output is correct
2 Correct 2 ms 12636 KB Output is correct
3 Correct 2 ms 12636 KB Output is correct
4 Correct 2 ms 12636 KB Output is correct
5 Correct 2 ms 12980 KB Output is correct
6 Correct 2 ms 12892 KB Output is correct
7 Correct 3 ms 12888 KB Output is correct
8 Correct 2 ms 12892 KB Output is correct
9 Incorrect 2 ms 12632 KB Output isn't correct
10 Halted 0 ms 0 KB -

Subtask #4
0 / 20.0

# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 12632 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #5
0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 12636 KB Output is correct
2 Correct 2 ms 12636 KB Output is correct
3 Correct 2 ms 12636 KB Output is correct
4 Correct 2 ms 12636 KB Output is correct
5 Correct 2 ms 12980 KB Output is correct
6 Correct 2 ms 12892 KB Output is correct
7 Correct 3 ms 12888 KB Output is correct
8 Correct 2 ms 12892 KB Output is correct
9 Correct 82 ms 47580 KB Output is correct
10 Correct 95 ms 56532 KB Output is correct
11 Correct 96 ms 57304 KB Output is correct
12 Correct 103 ms 56348 KB Output is correct
13 Correct 91 ms 57540 KB Output is correct
14 Correct 80 ms 47904 KB Output is correct
15 Correct 206 ms 57260 KB Output is correct
16 Correct 177 ms 56012 KB Output is correct
17 Correct 215 ms 60296 KB Output is correct
18 Correct 256 ms 60976 KB Output is correct
19 Correct 217 ms 59268 KB Output is correct
20 Correct 195 ms 64120 KB Output is correct
21 Correct 176 ms 63360 KB Output is correct
22 Correct 220 ms 63488 KB Output is correct
23 Correct 170 ms 62620 KB Output is correct
24 Correct 170 ms 59340 KB Output is correct
25 Correct 173 ms 64168 KB Output is correct
26 Correct 170 ms 62644 KB Output is correct
27 Correct 2 ms 12892 KB Output is correct
28 Correct 2 ms 12892 KB Output is correct
29 Correct 2 ms 12892 KB Output is correct
30 Correct 2 ms 12892 KB Output is correct
31 Correct 3 ms 12892 KB Output is correct
32 Incorrect 2 ms 12888 KB Output isn't correct
33 Halted 0 ms 0 KB -

Subtask #6
0 / 27.0

# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 12632 KB Output isn't correct
2 Halted 0 ms 0 KB -