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| #include <algorithm>
#include <cctype>
#include <cstdio>
#include <cstring>
#include <stack>
#include <vector>
template <typename T>
inline T& read(T& x) {
x = 0;
bool f = false;
short ch = getchar();
while (!isdigit(ch)) {
if (ch == '-') f = true;
ch = getchar();
}
while (isdigit(ch)) x = (x << 1) + (x << 3) + (ch ^ '0'), ch = getchar();
if (f) x = -x;
return x;
}
const int N = 7e4 + 5;
int n, m, heads[N], e_cnt, dep[N], siz[N], fa[N], son[N], top[N], ans[N];
struct Edge {
int nxt, v;
Edge() {}
Edge(int u, int v) : nxt(u), v(v) {}
} e[N << 1];
void add(int u, int v) {
e[++e_cnt].v = v, e[e_cnt].nxt = heads[u], heads[u] = e_cnt;
}
void dfs1(int u, int f) {
fa[u] = f, dep[u] = dep[f] + 1, siz[u] = 1;
for (int j = heads[u], v; j; j = e[j].nxt)
if ((v = e[j].v) != f) {
dfs1(v, u), siz[u] += siz[v];
if (siz[son[u]] < siz[v]) son[u] = v;
}
}
void dfs2(int u, int Top) {
top[u] = Top;
if (son[u]) dfs2(son[u], Top);
for (int j = heads[u], v; j; j = e[j].nxt)
if ((v = e[j].v) != fa[u] && v != son[u]) dfs2(v, v);
}
inline int getlca(int x, int y) {
while (top[x] != top[y]) {
if (dep[top[x]] < dep[top[y]]) std::swap(x, y);
x = fa[top[x]];
}
return dep[x] < dep[y] ? x : y;
}
inline int getdis(int x, int y) {
return dep[x] + dep[y] - (dep[getlca(x, y)] << 1);
}
struct Node {
int a, b, w;
Node() {}
Node(int a, int b, int w) : a(a), b(b), w(w) {}
inline void operator()(const Node& rhs) {
int tmp = getdis(a, rhs.a), orib = this->b;
if (w < tmp) this->b = rhs.a, this->w = tmp;
tmp = getdis(a, rhs.b);
if (w < tmp) this->b = rhs.b, this->w = tmp;
tmp = getdis(orib, rhs.a);
if (w < tmp) this->a = orib, this->b = rhs.a, this->w = tmp;
tmp = getdis(orib, rhs.b);
if (w < tmp) this->a = orib, this->b = rhs.b, this->w = tmp;
if (w < rhs.w) *this = rhs;
}
};
struct Segtree {
struct UFSNode {
Node s;
int fa, dep;
} p[N];
struct Node {
int u;
UFSNode p0;
Node(int u, const UFSNode& p0) : u(u), p0(p0) {}
};
std::vector<Edge> E[N << 2];
std::stack<Node> stk;
void insert(int x, int l, int r, int L, int R, const Edge& e) {
if (L <= l && r <= R) return E[x].emplace_back(e);
int mid = (l + r) >> 1;
if (L <= mid) insert(x << 1, l, mid, L, R, e);
if (mid < R) insert(x << 1 | 1, mid + 1, r, L, R, e);
}
int find(int u) { return u == p[u].fa ? u : find(p[u].fa); }
inline void merge(int u, int v, int& len) {
u = find(u), v = find(v);
if (u == v) return;
if (p[u].dep > p[v].dep) std::swap(u, v);
stk.push(Node(u, p[u])), stk.push(Node(v, p[v]));
p[v].s(p[u].s), p[u].fa = v;
if (p[u].dep == p[v].dep) ++p[v].dep;
len = std::max(len, p[v].s.w);
}
void solve(int x, int l, int r, int len) {
size_t ori = stk.size();
for (auto& i : E[x]) merge(i.nxt, i.v, len);
if (l == r) ans[l] = len;
else {
int mid = (l + r) >> 1;
solve(x << 1, l, mid, len);
solve(x << 1 | 1, mid + 1, r, len);
}
while (stk.size() != ori) {
p[stk.top().u] = stk.top().p0;
stk.pop();
}
}
} seg;
int main() {
#ifndef ONLINE_JUDGE
#ifdef LOCAL
freopen64("/tmp/CodeTmp/testdata.in", "r", stdin);
freopen64("/tmp/CodeTmp/testdata.out", "w", stdout);
#else
freopen("External.in", "r", stdin);
freopen("External.out", "w", stdout);
#endif
#endif
read(n), read(m);
for (int i = 1, u, v, l, r; i < n; ++i) {
read(u), read(v), read(l), read(r);
add(u, v), add(v, u);
seg.insert(1, 1, n, l, r, Edge(u, v));
}
dfs1(1, 0), dfs2(1, 1);
for (int i = 1; i <= n; ++i)
seg.p[i].fa = i, seg.p[i].dep = 1, seg.p[i].s = Node(i, i, 0);
seg.solve(1, 1, n, 0);
for (int i = 1, x; i <= m; ++i) printf("%d\n", ans[read(x)]);
return 0;
}
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