52 lines
1.0 KiB
C++
52 lines
1.0 KiB
C++
#include <cstdio>
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#include <algorithm>
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#include <cstring>
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#include <vector>
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using namespace std;
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#define maxn 1005
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int head[maxn],tot,u,v,n;
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struct Edge
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{
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int to,next;
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}e[maxn*2];
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void addedge(int u,int v)
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{
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e[tot].to=v;
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e[tot].next=head[u];
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head[u]=tot++;
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}
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int dfs(int u,int pre)
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{
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int ans=-1,cnt=0;
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vector<int> check;
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for(int i=head[u];i!=-1;i=e[i].next)
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{
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int v=e[i].to,t;
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if(v==pre) continue;
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t=dfs(v,u);
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check.push_back(t);
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ans=max(ans,t);
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}
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if(check.size()==0) return 1;
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for(int i=0;i<check.size();i++) if(check[i]==ans) cnt++;
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if(cnt>1) return ans+1;
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else return ans;
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}
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int main()
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{
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int n;
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while(scanf("%d",&n)!=EOF)
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{
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tot=0;
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memset(head,-1,sizeof(head));
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for(int i=0;i<n-1;i++)
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{
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scanf("%d%d",&u,&v);
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addedge(u,v);
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addedge(v,u);
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}
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int ans=dfs(1,0);
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printf("%d\n",ans);
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}
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}
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