#include <bits/stdc++.h>
#define DB double
#define LL long long

#define MST(a, b) memset((a), (b), sizeof(a))
#define MRK() cout << "Mark" << endl;
#define WRT(x) cout << #x << " = " << (x) << endl;

#define MAXN 5010
#define MAXM 410000
#define MOD 998244353
#define INF 0x3f3f3f3f
#define LLINF 0x3f3f3f3f3f3f3f3f
#define EPS 1e-5

#define _ 0
using namespace std;

vector<int> g[MAXN];
int pool[MAXN][MAXN << 1];
int *dp[MAXN];
int n;
int col[MAXN], size[MAXN];

void init() {
    int x, y;
    cin >> n;
    for (int i = 1; i < n; i++) {
        scanf("%d%d", &x, &y);
        g[x].push_back(y);
        g[y].push_back(x);
    }
    for (int i = 1; i <= n; i++) dp[i] = pool[i] + MAXN;
    col[1] = -1;
}

void dfs(int pos, int f) {
    col[pos] = -col[f];
    for (auto p : g[pos])
        if (p != f) {
            dfs(p, pos);
            size[pos] += size[p];
        }
}

void clear(int *p, int n) {
    for (int i = -n; i <= n; i++) p[i] = -INF;
}

int tpool[MAXN << 1];
int *tmp = tpool + MAXN;

void work(int pos, int f) {
    int mx = -INF;
    size[pos] = 1;
    clear(dp[pos], size[pos]);
    dp[pos][col[pos]] = 0;
    for (auto p : g[pos])
        if (p != f) {
            work(p, pos);
            clear(tmp, size[pos] + size[p]);
            for (int i = -size[pos]; i <= size[pos]; i++)
                for (int j = -size[p]; j <= size[p]; j++) tmp[i + j] = max(tmp[i + j], dp[pos][i] + dp[p][j]);
            size[pos] += size[p];
            for (int i = -size[pos]; i <= size[pos]; i++) dp[pos][i] = tmp[i];
        }
    for (int i = -size[pos]; i <= size[pos]; i++) dp[pos][0] = max(dp[pos][0], dp[pos][i] + i * i);
}

int main() {
    init();
    dfs(1, 1);
    work(1, 1);
    cout << (dp[1][0] - n);
    return ~~(0 ^ _ ^ 0);
}