#include<bits/stdc++.h> using namespace std; const int N=1e4+5; struct edge{ int to,w; }; int dp[N][N],son[N],f[N][N]; vector<edge>G[N]; int n,k,x; inline void dfs(int u,int fa){ son[u]=1; dp[u][0]=dp[u][1]=0; for(auto v:G[u]){ if(v.to==fa) continue; dfs(v.to,u);son[u]+=son[v.to]; for(int i=min(k,son[u]);i>=1;i--) for(int j=min(i-1,son[v.to]);j>=1;j--){ if(dp[u][i]-f[u][i]>=dp[u][i-j]+dp[v.to][j]+v.w*2-max(f[u][i-j],f[v.to][j]+v.w)){ dp[u][i]=dp[u][i-j]+dp[v.to][j]+v.w*2; f[u][i]=max(f[u][i-j],f[v.to][j]+v.w); } } } } int main(){ memset(dp,0x3f,sizeof dp); scanf("%d%d%d",&n,&k,&x); for(int i=1;i<n;i++){ int u,v,w;scanf("%d%d%d",&u,&v,&w); G[u].push_back({v,w});G[v].push_back({u,w}); } dfs(x,0); printf("%d",dp[x][k]-f[x][k]); return 0; }

museum.cpp: In function 'int main()':
museum.cpp:27:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   27 |  scanf("%d%d%d",&n,&k,&x);
      |  ~~~~~^~~~~~~~~~~~~~~~~~~
museum.cpp:29:18: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   29 |   int u,v,w;scanf("%d%d%d",&u,&v,&w);
      |             ~~~~~^~~~~~~~~~~~~~~~~~~