#include <bits/stdc++.h>
#define fi first
#define se second
#define INF (int)(1e9)
using namespace std;
vector<vector<pair<int,int> > > vec;
bool vis[100005];
int maxi=0,A,idx=0;
pair<int,int> p[100005],center[100005];
vector<int> nodes;
void dfs(int node,int d){
//debug(node);
//debugs(d,maxi);
nodes.push_back(node);
if(d>maxi)
A=node,maxi=d;
vis[node]=1;
for(auto child:vec[node])
if(child.fi!=p[node].fi){
vis[child.fi]=1;
p[child.fi]={node,child.se};
dfs(child.fi,d+child.se);
}
}
vector<pair<int,int> > tree_d;
pair<int,int> findCenter(int node){
maxi=0;
dfs(node,0);
//debug(maxi);
for(auto i:nodes)
p[i]={-1,-1};
nodes.clear();
int B=A,sum=0,mini=INF,c=node,sh=INF;
maxi=0;
dfs(B,0);
nodes.clear();
//debugs(node,maxi);debugs(A,B);
for(;A!=-1;sum+=p[A].se,A=p[A].fi){
//debugs(A,sum);
if(abs(maxi/2-sum)<mini)
mini=abs(maxi/2-sum),c=A,sh=sum;
}
//debugs(c,);
//sep()
tree_d.push_back({maxi,idx});
return {c,max(maxi-sh,0)};
}
int travelTime(int N, int M, int L, int A[], int B[], int T[]) {
vec.resize(N);
for (int i = 0; i < M; ++i)
{
//debug(A[i]);
vec[A[i]].push_back({B[i],T[i]});
vec[B[i]].push_back({A[i],T[i]});
}
//debug(1);
for (int i = 0; i < N; ++i)
if(!vis[i])
center[idx++]=findCenter(i);
sort(tree_d.begin(),tree_d.end(),greater<pair<int,int> >());
int centroid=center[0].first,ans=tree_d[0].fi,max_d=0;
for (int i = 0; i < idx-1; ++i)
{
//max_d=max(max_d,center[tree_d[i+1].se].se);
//max_d=max(max_d,center[tree_d[i].se].se);
if(center[tree_d[i+1].se].se>center[tree_d[i].se].se)
centroid=center[tree_d[i+1].se].fi;
ans=max(ans,center[tree_d[i+1].se].se+center[tree_d[i].se].se+2);
//debug(ans);
//ans=max(ans,max_d)
}
return ans;
}
Compilation message
dreaming.cpp: In function 'int travelTime(int, int, int, int*, int*, int*)':
dreaming.cpp:61:6: warning: variable 'centroid' set but not used [-Wunused-but-set-variable]
int centroid=center[0].first,ans=tree_d[0].fi,max_d=0;
^~~~~~~~
dreaming.cpp:61:48: warning: unused variable 'max_d' [-Wunused-variable]
int centroid=center[0].first,ans=tree_d[0].fi,max_d=0;
^~~~~
/tmp/ccjKYcHB.o: In function `main':
grader.c:(.text.startup+0xa2): undefined reference to `travelTime'
collect2: error: ld returned 1 exit status
