#include<bits/stdc++.h>
#include "swap.h"
#define MAXN 100007
using namespace std;
const int inf=1e9+7;
int n,m,a[MAXN],b[MAXN],c[MAXN],dep[MAXN];
vector< pair<int,int> > tree[MAXN];
vector<int> v[MAXN];
int parent[MAXN],res[MAXN];
struct info{
int par,mins,maxe;
};
struct edge{
int from,to,cost;
inline friend bool operator < (edge fr,edge sc){
return fr.cost<sc.cost;
}
}e[MAXN];
struct unionfind{
int dsu[MAXN],sz[MAXN];
void init(){
for(int i=1;i<=n;i++){
dsu[i]=i; sz[i]=1;
}
}
int root(int x){
if(dsu[x]==x)return dsu[x];
return root(dsu[x]);
}
void mergev(int x,int y){
int rootx=root(x);
int rooty=root(y);
if(rootx==rooty)return;
if(sz[rootx]<sz[rooty])swap(rootx,rooty);
dsu[rooty]=rootx;
sz[rootx]+=sz[rooty];
}
bool connected(int x,int y){
return root(x)==root(y);
}
}graph;
info dp[MAXN][20];
void dfs(int x,int p,int ee){
parent[x]=p;
dep[x]=dep[p]+1;
for(pair<int,int> i:tree[x]){
if(i.first==p)continue;
dfs(i.first,x,i.second);
}
dp[x][0].par=parent[x];
dp[x][0].mins=res[x];
dp[x][0].maxe=ee;
for(int t=1;t<20;t++){
dp[x][t].par=dp[dp[x][t-1].par][t-1].par;
dp[x][t].mins=min( dp[x][t-1].mins , dp[dp[x][t-1].par][t-1].mins );
dp[x][t].maxe=max( dp[x][t-1].maxe , dp[dp[x][t-1].par][t-1].maxe );
}
}
int getbranch(int x,int y){
int ans=inf;
if(dep[x]<dep[y])swap(x,y);
if(x==y or parent[x]==y)return inf;
if(dep[x]!=dep[y]){
x=parent[x];
for(int i=19;i>=0;i--){
if(dep[x]-dep[y]>(1<<i)){
ans=min(ans,dp[x][i].mins);
x=dp[x][i].par;
}
}
if(parent[x]==y)return ans;
if(dep[x]>dep[y]){
x=parent[x];
ans=min(ans,res[x]);
}
}
x=parent[x];
y=parent[y];
ans=min(ans,res[x]);
for(int i=19;i>=0;i--){
if(dp[x][i].par!=0 and dp[y][i].par!=0 and dp[x][i].par!=dp[y][i].par){
ans=min(ans,dp[x][i].mins);
ans=min(ans,dp[y][i].mins);
x=dp[x][i].par; y=dp[y][i].par;
}
}
if(x!=y)ans=min(ans,res[parent[x]]);
return ans;
}
int getedge(int x,int y){
if(dep[x]>dep[y])swap(x,y);
int ans=0;
for(int i=19;i>=0;i--){
if(dep[x]-dep[y]>(1<<i)){
ans=max(ans,dp[x][i].maxe);
x=dp[x][i].par;
}
}
if(parent[x]==y)return ans;
ans=max(ans,dp[x][0].maxe);
x=dp[x][0].par;
for(int i=19;i>=0;i--){
if(dp[x][i].par!=0 and dp[y][i].par!=0 and dp[x][i].par!=dp[y][i].par){
ans=max(ans,dp[x][i].maxe);
ans=max(ans,dp[y][i].maxe);
x=dp[x][i].par; y=dp[y][i].par;
}
}
return ans;
}
void init(int N, int M,vector<int> U, vector<int> V, vector<int> W) {
n=N; m=M;
for(int i=1;i<=m;i++){
a[i]=U[i-1]+1; b[i]=V[i-1]+1; c[i]=W[i-1];
v[a[i]].push_back(c[i]);
v[b[i]].push_back(c[i]);
e[i]={a[i],b[i],c[i]};
}
for(int i=1;i<=n;i++){
sort(v[i].begin(),v[i].end());
res[i]=inf;
if(v[i].size()>=3)res[i]=v[i][2];
}
res[0]=inf;
sort(e+1,e+m+1);
graph.init();
for(int i=1;i<=m;i++){
if(graph.connected(e[i].from,e[i].to))continue;
tree[e[i].from].push_back({e[i].to,e[i].cost});
tree[e[i].to].push_back({e[i].from,e[i].cost});
graph.mergev(e[i].from,e[i].to);
}
dfs(1,0,0);
}
int getMinimumFuelCapacity(int X, int Y) {
int ans=getbranch(X+1,Y+1);
if(ans==inf)return -1;
return ans;
}
/*
int main(){
init(5, 6, {0, 0, 1, 1, 1, 2}, {1, 2, 2, 3, 4, 3}, {4, 4, 1, 2, 10, 3});
cout<<getMinimumFuelCapacity(1, 2)<<"\n";
cout<<getMinimumFuelCapacity(2,4)<<"\n";
cout<<getMinimumFuelCapacity(0,1)<<"\n";
}
*/
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
8540 KB |
Output is correct |
2 |
Correct |
1 ms |
8540 KB |
Output is correct |
3 |
Correct |
1 ms |
8540 KB |
Output is correct |
4 |
Incorrect |
1 ms |
8796 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
8540 KB |
Output is correct |
2 |
Correct |
1 ms |
8540 KB |
Output is correct |
3 |
Incorrect |
91 ms |
44004 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
8540 KB |
Output is correct |
2 |
Correct |
1 ms |
8540 KB |
Output is correct |
3 |
Correct |
1 ms |
8540 KB |
Output is correct |
4 |
Incorrect |
1 ms |
8796 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
8540 KB |
Output is correct |
2 |
Correct |
1 ms |
8540 KB |
Output is correct |
3 |
Correct |
1 ms |
8540 KB |
Output is correct |
4 |
Incorrect |
1 ms |
8796 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
8540 KB |
Output is correct |
2 |
Correct |
1 ms |
8540 KB |
Output is correct |
3 |
Correct |
1 ms |
8540 KB |
Output is correct |
4 |
Incorrect |
1 ms |
8796 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
8540 KB |
Output is correct |
2 |
Correct |
1 ms |
8540 KB |
Output is correct |
3 |
Correct |
1 ms |
8540 KB |
Output is correct |
4 |
Incorrect |
1 ms |
8796 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |