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| #include<cstdio> #include<algorithm> #define RG register #define file(x) freopen(#x".in", "r", stdin);freopen(#x".out", "w", stdout);
inline int read() { int data=0, w=1; char ch=getchar(); while(ch!='-'&&(ch<'0'||ch>'9')) ch=getchar(); if(ch=='-') w=-1, ch=getchar(); while(ch>='0'&&ch<='9') data=data*10+(ch^48), ch=getchar(); return data*w; }
const int maxn(100010); struct node { node *son[2]; int max, id; } *root[maxn], pool[maxn * 50], *pos; struct edge { int next, to; } e[maxn << 1]; struct query { int next, to, id; } q[maxn << 1]; struct answer { int a, b, v, lca; } ans[maxn]; bool vis[maxn]; int head[maxn], e_num, fa[maxn], n, m, s, qhead[maxn], q_num, F[maxn], Ans[maxn]; inline void add_edge(int from, int to) { e[++e_num] = (edge) {head[from], to}; head[from] = e_num; } inline void add_query(int from, int to, int id) { q[++q_num] = (query) {qhead[from], to, id}; qhead[from] = q_num; } inline int find(int x) { return fa[x] == x ? x : fa[x] = find(fa[x]); }
void dfs(int x) { vis[x] = true; for(RG int i = head[x]; i; i = e[i].next) { int to = e[i].to; if(to == F[x]) continue; F[to] = x; dfs(to); fa[find(to)] = find(x); }
for(RG int i = qhead[x]; i; i = q[i].next) { int to = q[i].to; if(!vis[to]) continue; ans[q[i].id].lca = find(to); } }
inline int Max(node *x) { return x ? x -> max : 0; } inline int Id(node *x) { return x ? x -> id : 0; } inline void pushup(node *x) { if(Max(x -> son[0]) >= Max(x -> son[1])) x -> max = Max(x -> son[0]), x -> id = Id(x -> son[0]); else x -> max = Max(x -> son[1]), x -> id = Id(x -> son[1]); if(!x -> max) x -> id = 0; }
inline void Insert(node *&x, int pos, int val, int l = 1, int r = maxn - 10) { if(!x) x = ::pos++; if(l == r) { x -> max += val; x -> id = l; if(!x -> max) x -> id = 0; return; } int mid = (l + r) >> 1; if(pos <= mid) Insert(x -> son[0], pos, val, l, mid); else Insert(x -> son[1], pos, val, mid + 1, r); pushup(x); if(!x -> max) x -> id = 0; }
inline node *Merge(node *x, node *&y, int l = 1, int r = maxn - 10) { if(!x) return y; if(!y) return x; int mid = (l + r) >> 1; if(l == r) { x -> max += y -> max; x -> id = l; return x; } x -> son[0] = Merge(x -> son[0], y -> son[0], l, mid); x -> son[1] = Merge(x -> son[1], y -> son[1], mid + 1, r); pushup(x); return x; }
void solve(int x) { for(RG int i = head[x]; i; i = e[i].next) { int to = e[i].to; if(to == F[x]) continue; solve(to); root[x] = Merge(root[x], root[to]); }
Ans[x] = Id(root[x]); }
int main() { #ifndef ONLINE_JUDGE file(cpp); #endif
pos = pool; n = read(); m = read(); for(RG int i = 1, a, b; i < n; i++) a = read(), b = read(), add_edge(a, b), add_edge(b, a); for(RG int i = 1; i <= n; i++) fa[i] = i; for(RG int i = 1, a, b, c; i <= m; i++) a = read(), b = read(), c = read(), ans[i] = (answer) {a, b, c, 0}, add_query(a, b, i), add_query(b, a, i); dfs(1); for(RG int i = 1; i <= m; i++) Insert(root[ans[i].a], ans[i].v, 1), Insert(root[ans[i].b], ans[i].v, 1), Insert(root[ans[i].lca], ans[i].v, -1), Insert(root[F[ans[i].lca]], ans[i].v, -1); solve(1); for(RG int i = 1; i <= n; i++) printf("%d\n", Ans[i]); return 0; }
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