// Problem: Parmigiana With Seafood
// Contest: Luogu
// URL: https://www.luogu.com.cn/problem/CF1776M
// Memory Limit: 250 MB
// Time Limit: 2000 ms
//
// Powered by CP Editor (https://cpeditor.org)

#include <bits/stdc++.h>
using namespace std;
const int maxn = 100010;
vector<int> G[maxn];
int col[maxn];
int f[maxn];
int a[maxn];
int n;
int ans;
void dfs(int u, int fa) {
    col[u] = col[fa] ^ 1;
    f[u] = fa;
    for (int v : G[u]) {
        if (v == fa)
            continue;
        dfs(v, u);
    }
}
void dfs2(int u) {
    if (col[u] == col[n])
        a[u] = u;
    int m1 = 0, m2 = 0;
    for (int v : G[u]) {
        if (v == f[u])
            continue;
        dfs2(v);
        a[u] = max(a[u], a[v]);
        if (a[v] >= m1) {
            m2 = m1;
            m1 = a[v];
        } else if (a[v] >= m2) {
            m2 = a[v];
        }
    }
    ans = max(ans, min(m1, m2));
}
int m0, m1;
int main() {
    scanf("%d", &n);
    for (int i = 1; i < n; i++) {
        int u, v;
        scanf("%d %d", &u, &v);
        G[u].emplace_back(v);
        G[v].emplace_back(u);
    }
    if (!(n & 1)) {
        printf("%d", n);
        return 0;
    }
    dfs(n, 0);
    dfs2(n);
    for (int i = n; i > 0; i--) {
        if (col[i] && !m1) {
            m1 = i;
        }
        if (!col[i] && !m0) {
            m0 = i;
        }
        if (G[i].size() <= 1 || col[i] != col[n]) {
            ans = max(ans, i);
        }
    }
    printf("%d", ans);
}