제출 #41018

#제출 시각아이디문제언어결과실행 시간메모리
41018Hassoony경주 (Race) (IOI11_race)C++14
컴파일 에러
0 ms0 KiB
#include<bits/stdc++.h> #include<unordered_map> using namespace std; typedef double D; typedef long long ll; const ll mod=1e9+7; const ll inf=(1ll<<62); const int SQ=400; const int MX=2e5+9; int n,a,b,subtree[MX],blocked[MX],par[MX],depth[MX],k,dis[MX]; vector<pair<int,int> >v[MX]; vector<int>f; ll ans=0; unordered_map<int,int>cnt; void dfs_size(int x,int p){ subtree[x]=1;par[x]=p; for(auto pp:v[x]){ if(pp.first==p||blocked[pp.first])continue; dfs_size(pp.first,x); subtree[x]+=subtree[pp.first]; } } vector<int>nodes; void DFS(int x,int p,int sum){ if(sum>k)return; f.push_back(x); nodes.push_back(x); dis[x]=sum; for(auto pp:v[x]){ if(pp.first==p||blocked[pp.first])continue; depth[pp.first]=depth[x]+1; DFS(pp.first,x,sum+pp.second); } } void create(int x){ dfs_size(x,-1); int S=subtree[x],idx; queue<int>q; q.push(x); while(!q.empty()){ int nxt=q.front();q.pop(); int s=subtree[x]-subtree[nxt]; for(auto pp:v[nxt]){ if(pp.first==par[nxt]||blocked[pp.first])continue; s=max(s,subtree[pp.first]); q.push(pp.first); } if(S>s){ S=s; idx=nxt; } } for(auto pp:f){ cnt[dis[pp]]=0; dis[pp]=depth[pp]=0; } f.clear(); blocked[idx]=1; cnt[0]=0; dis[idx]=depth[idx]=0; for(auto pp:v[idx]){ if(blocked[pp.first])continue; depth[pp.first]=1; DFS(pp.first,idx,pp.second); for(auto nxt:nodes){ if(k-dis[nxt]<0)continue; if(dis[nxt]==k)ans=min(ans,(ll)depth[nxt]); if(cnt[k-dis[nxt]]==0)continue; ans=min(ans,(ll)depth[nxt]+cnt[k-dis[nxt]]); } for(auto i:nodes){ if(cnt[dis[i]]==0){cnt[dis[i]]=depth[i];} else cnt[dis[i]]=min(cnt[dis[i]],depth[i]); } nodes.clear(); } // cout<<"answer: "<<ans<<endl; for(auto pp:v[idx]){ if(blocked[pp.first])continue; create(pp.first); } } int c; int main(){ scanf("%d%d",&n,&k); for(int i=0;i<n-1;i++){ scanf("%d%d%d",&a,&b,&c); v[a].push_back({b,c}); v[b].push_back({a,c}); } ans=inf; create(1); if(ans==inf)puts("-1"); else cout<<ans<<endl; }

컴파일 시 표준 에러 (stderr) 메시지

race.cpp: In function 'int main()':
race.cpp:85:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d",&n,&k);
     ~~~~~^~~~~~~~~~~~~~
race.cpp:87:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d%d",&a,&b,&c);
         ~~~~~^~~~~~~~~~~~~~~~~~~
race.cpp: In function 'void create(int)':
race.cpp:37:22: warning: 'idx' may be used uninitialized in this function [-Wmaybe-uninitialized]
     int S=subtree[x],idx;
                      ^~~
/tmp/ccMPJJCS.o: In function `main':
race.cpp:(.text.startup+0x0): multiple definition of `main'
/tmp/ccb6ClrY.o:grader.cpp:(.text.startup+0x0): first defined here
/tmp/ccb6ClrY.o: In function `main':
grader.cpp:(.text.startup+0x20): undefined reference to `best_path(int, int, int (*) [2], int*)'
collect2: error: ld returned 1 exit status