#include <bits/stdc++.h>
#define ll long long
#define ld double
#define ull unsigned long long
#define pb push_back
#define pll pair<ll, ll>
#define pii pair<int, int>
#define fi first
#define se second
using namespace std;
const int N = 1e6+5;
const int M = 1e2+2;
const ll base = 1e4;
const ll mod = 998244353;
const int inf = 1e9;
const double ex = 1e-9;
int k, t, n;
int a[N], b[N], tong, m, ans;
pii mx[N];
vector<int> vi, adj[N];
mt19937_64 mt(chrono::steady_clock::now().time_since_epoch().count());
double p[N][N], res[N], q[N];
void upd(int u, int x)
{
if(x > mx[u].fi)mx[u].fi = x;
else if(x > mx[u].se)mx[u].se = x;
}
void dfs(int u, int p = 0)
{
for(int v: adj[u])
{
if(v == p)continue;
dfs(v, u);
if(a[v] == 1)upd(u, mx[v].fi+1);
}
}
void dfs1(int u, int p = 0)
{
for(int v: adj[u])
{
if(v == p)continue;
if(a[u] == 1)
{
if(mx[u].fi != mx[v].fi+1)upd(v, mx[u].fi+1);
else upd(v, mx[u].se+1);
}
dfs1(v, u);
}
}
void sol(int icase)
{
cin >> n;
for(int i = 1; i < n; i ++)
{
int x, y;
cin >> x >> y;
adj[x].pb(y);
adj[y].pb(x);
}
for(int i = 1; i <= n; i ++)cin >> a[i];
dfs(1);
dfs1(1);
pii res;
res.fi = inf;
res.se = 1;
for(int u = 1; u <= n; u ++)
{
//cout << a[u] <<" "<<mx[u].fi<<" "<<mx[u].se<<'\n';
if(1ll * res.fi * (mx[u].fi+mx[u].se+1) > 1ll * a[u] * res.se)
{
res.fi = a[u];
res.se = mx[u].se+mx[u].fi+1;
}
}
k = __gcd(res.fi, res.se);
res.fi /= k;
res.se /= k;
cout << res.fi <<"/"<<res.se;
}
int main()
{
cin.tie(0);
cout.tie(0);
ios_base::sync_with_stdio(0);
#define task "test"
if(fopen(task".inp", "r"))
{
freopen(task".inp", "r", stdin);
freopen(task".out", "w", stdout);
}
int test = 1;
//cin >> test;
for(int i = 1; i <= test; i ++)sol(i);
return 0;
}
Compilation message
mag.cpp: In function 'int main()':
mag.cpp:90:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
90 | freopen(task".inp", "r", stdin);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
mag.cpp:91:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
91 | freopen(task".out", "w", stdout);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
/usr/bin/ld: failed to convert GOTPCREL relocation; relink with --no-relax
collect2: error: ld returned 1 exit status
