#include <iostream>
#include <string>
#include <cstring>
#include <vector>
#include <map>
#include <set>
#include <algorithm>
#include <math.h>
#include <cstdio>
#include <stdio.h>
#include <queue>
#include <deque>
using namespace std;
#define max3(a, b, c) max(a, max(b, c))
#define min3(a, b, c) min(a, min(b, c))
#define mp make_pair
#define f first
#define se second
#define pb push_back
#define ppb pop_back
#define ll long long
#define ull unsigned long long
#define cntbit(x) __builtin_popcount(x)
#define endl '\n'
#define uset unordered_set
#define umap unordered_map
#define pii pair<long long, long long>
#define ld long double
#define pll pair<long long, long long>
#define int long long
const int inf = 2e9;
const int N = 2e5 + 15;
int n, mx, parent[N], sz;
pii d[N], ans;
vector <int> g[N], cycle;
bool used[N], is[N];
map <int, int> cnt;
multiset <int> cur;
bool find_cycle(int v, int p = -1) {
used[v] = true;
parent[v] = p;
for(int to : g[v]) {
if(to != p) {
if(used[to]) {
int u = v;
is[u] = true;
cycle.pb(u);
while(u != to) {
u = parent[u];
cycle.pb(u);
is[u] = true;
}
return true;
}
else if(find_cycle(to, v))
return true;
}
}
return false;
}
inline void combine(pii &a, pii b) {
if(a.f == b.f)
a.se += b.se;
else if(a.f < b.f)
a = b;
}
void dfs_tree(int v, int p = -1) {
d[v] = mp(0, 1);
for(int to : g[v])
if(to != p && !is[to]) {
dfs_tree(to, v);
++d[to].f;
combine(ans, mp(d[v].first + d[to].first, d[v].second * d[to].second));
combine(d[v], d[to]);
}
}
#undef int
int main() {
#define int long long
cin >> n;
for(int i = 1; i <= n; ++i) {
int u, v;
cin >> u >> v;
g[u].pb(v);
g[v].pb(u);
}
find_cycle(1);
sz = cycle.size();
for(int i : cycle)
dfs_tree(i);
for(int i = 0; i < sz + sz/2; ++i) {
if(i >= sz/2)
combine(ans, mp(d[cycle[i % sz]].f + i + *cur.rbegin(), 0)),
cur.erase(cur.find(d[cycle[i - sz/2]].f - i + sz/2));
cur.insert(d[cycle[i % sz]].f - i);
}
for(int i = 0; i < sz + sz/2; ++i) {
if(i >= sz / 2)
ans.se += d[cycle[i % sz]].se * cnt[ans.f - d[cycle[i % sz]].f - i],
cnt[d[cycle[i - sz/2]].f - i + sz/2] -= d[cycle[i - sz/2]].se;
cnt[d[cycle[i % sz]].f - i] += d[cycle[i % sz]].se;
}
cout << ans.se << endl;
return 0;
}
