C++ :

#include <bits/stdc++.h>
#define LL long long 
using namespace std;
const int maxn=2*1e5+100;
LL v[maxn],ver[maxn],edge[maxn],nextr[maxn],head[maxn],sum[maxn],trie[2][maxn*16];
int n,tot=1;

inline LL read()//快速读入
{
    char ch=getchar();
    int p=1,q=0;
    for(; ch!='-' && ch<'0' || ch>'9'; ch=getchar());
    if (ch=='-')
        p=-p;
    for(; ch>='0' && ch<='9'; q=q*10+ch-'0',ch=getchar());
    return p*q;
}

inline void add(int x,int y,int z){
	ver[++tot] = y,edge[tot] = z;
	nextr[tot] = head[x],head[x] = tot;
}

inline void dfs(int x){
	v[x] = 1;
	for (int i=head[x];i;i=nextr[i]){
		if (!v[ver[i]]){
			sum[ver[i]] = sum[x] ^ edge[i];
			dfs(ver[i]);
		}
	}
}

inline void insert(int x){
	int p = 1;
	for (int k=31;k>=0;k--){
		int ch = x >>k &1;
		if (trie[ch][p] == 0) trie[ch][p] =++tot;
		p = trie[ch][p];
	}
}

inline LL search(int x){
	LL p = 1,ans = 0;
	for (int k=31;k>=0;k--){
		int ch = x>>k&1;
		if (trie[ch^1][p]) {
			p = trie[ch^1][p];
			ans|=(1<<k);
		}else{
			p = trie[ch][p];
		}
	}
	return ans;
}

int main(){
	cin >> n;
	memset(v,0,sizeof(v));
	for (int i=1;i<n;i++){
		LL x,y,z;
		x = read(),y = read(),z = read();
		x++,y++;
		add(x,y,z);
		add(y,x,z);
	}
	memset(sum,0,sizeof(sum));
	dfs(1);
	tot =1;
	LL ans  = 0;
	for (int i=1;i<=n;i++){
		insert(sum[i]);
		ans = max(ans,search(sum[i]));
	}
	cout << ans ;

}