#include<map>
#include<cmath>
#include<stack>
#include<queue>
#include<cstdio>
#include<cctype>
#include<vector>
#include<cstdlib>
#include<cstring>
#include<iostream>
#include<algorithm>
using namespace std;
typedef long long ll;
const int N=5005;
const int INF=1e9;
inline int read(){int X=0,w=0;char ch=0;while(!isdigit(ch)){w|=ch=='-';ch=getchar();}while(isdigit(ch))X=(X<<3)+(X<<1)+(ch^48),ch=getchar();return w?-X:X;
}
struct node{int w,to,nxt;
}e[N*2];
int n,cnt,head[N],f[N][3];
bool vis[N];
inline void add(int u,int v,int w){e[++cnt].to=v;e[cnt].w=w;e[cnt].nxt=head[u];head[u]=cnt;
}
int ans;
void dfs1(int u,int fa){for(int i=head[u];i;i=e[i].nxt){int v=e[i].to,w=e[i].w;if(vis[v]||fa==v)continue;dfs1(v,u);if(f[u][0]<f[v][0]+w){f[u][1]=f[u][0];f[u][0]=f[v][0]+w;}else if(f[u][1]<f[v][0]+w)f[u][1]=f[v][0]+w;}ans=max(ans,f[u][0]+f[u][1]);
}
void dfs2(int u,int fa){for(int i=head[u];i;i=e[i].nxt){int v=e[i].to,w=e[i].w;if(vis[v]||fa==v)continue;f[v][2]=f[u][2]+w;if(f[u][0]-w!=f[v][0])f[v][2]=max(f[v][2],f[u][0]+w);else f[v][2]=max(f[v][2],f[u][1]+w);dfs2(v,u);}ans=min(ans,max(f[u][0],f[u][2]));
}
int main(){n=read();for(int i=1;i<n;i++){int u=read(),v=read(),w=read();add(u,v,w);add(v,u,w);}int sum=INF;for(int i=1;i<=cnt;i+=2){int u=e[i].to,v=e[i+1].to,w=e[i].w;int w1,w2,tmp=0;vis[v]=1;memset(f,0,sizeof(f));ans=0;dfs1(u,0);tmp=max(tmp,ans);ans=INF;dfs2(u,0);w1=ans;vis[v]=0;vis[u]=1;ans=0;dfs1(v,0);tmp=max(tmp,ans);ans=INF;dfs2(v,0);w2=ans;vis[u]=0;tmp=max(tmp,w1+w2+w);sum=min(sum,tmp);}printf("%d\n",sum);return 0;
}