#include <iostream>#include <cstdio>#include <cstring>#include <cstdlib>#include <vector>using namespace std;const int MAXN = 205;typedef pair<int,int> Edge;vector<Edge> adj[MAXN];bool del[MAXN];int st[MAXN], ed[MAXN];int n;void load() {    scanf("%d", &n);    for (int i = 1; i < n; ++i) {        int a, b;        scanf("%d%d", &a, &b);        adj[a].push_back(make_pair(b,i));        adj[b].push_back(make_pair(a,i));        st[i] = a;        ed[i] = b;    }}int used[MAXN];int dis[MAXN];int farthest;void dfs(int u) {    used[u] = true;    for (vector<Edge>::iterator itr = adj[u].begin(); itr != adj[u].end(); ++itr) {        int v = itr->first;        int id = itr->second;        if (0 == del[id] && 0 == used[v]) {            dis[v] = dis[u]+1;            if (dis[v] > dis[farthest])                farthest = v;            dfs(v);        }    }}void work() {    int ans = 0;    for (int t= 1; t < n; ++t) {        memset(used,0,sizeof(used));        memset(dis,0,sizeof(dis));        del[t] = true;        farthest = st[t];        dfs(st[t]);        memset(used,0,sizeof(used));        memset(dis,0,sizeof(dis));        dfs(farthest);        int tans = dis[farthest];        memset(dis,0,sizeof(dis));        memset(used,0,sizeof(used));        farthest = ed[t];        dfs(ed[t]);        memset(dis,0,sizeof(dis));        memset(used,0,sizeof(used));        dfs(farthest);        tans *= dis[farthest];        if (tans > ans)            ans = tans;        del[t] = false;    }    printf("%d\n", ans);}int main() {    load();    work();    return 0;}