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| #include <cstdio>
#define INF 2147483647
#define maxN 100010
struct tree{ int min, tag; } a[maxN << 2];
struct edge{ int x, y, c, g; } b[maxN << 1];
int len = 0, n = 0, m = 0;
int Ans[maxN];
int number[maxN], top[maxN];
int f[maxN][20], size[maxN], son[maxN], dep[maxN], bh[maxN], h[maxN];
int Min (int x, int y)
{
return x < y ? x : y;
}
void build (int now, int l, int r)
{
a[now].min = a[now].tag = INF;
if(l < r)
{
int mid = (l + r) >> 1;
build(now << 1, l, mid);
build(now << 1 | 1, mid + 1, r);
}
}
void ins (int x, int y)
{
len++;
b[len].x = x;
b[len].y = y;
b[len].c = (len + 1) / 2;
b[len].g = h[x];
h[x] = len;
}
void dfs1 (int x)
{
for(int i = h[x];i;i = b[i].g)
{
int y = b[i].y;
if(!dep[y])
{
f[y][0] = x;
bh[y] = b[i].c;
dep[y] = dep[x] + 1;
dfs1(y);
size[x] += size[y];
if(size[y] > size[son[x]])
{
son[x] = y;
}
}
}
size[x]++;
}
void dfs2 (int x)
{
number[x] = ++number[0];
if(son[x])
{
top[son[x]] = top[x];
dfs2(son[x]);
}
for(int i = h[x];i;i = b[i].g)
{
int y = b[i].y;
if(dep[x] + 1 == dep[y] && y != son[x])
{
top[y] = y;
dfs2(y);
}
}
}
void pushdown (int now, int l, int r)
{
if(a[now].tag != INF)
{
if(l < r)
{
a[now << 1].min = Min(a[now << 1].min, a[now].tag);
a[now << 1 | 1].min = Min(a[now << 1 | 1].min, a[now].tag);
a[now << 1].tag = Min(a[now << 1].tag, a[now].tag);
a[now << 1 | 1].tag = Min(a[now << 1 | 1].tag, a[now].tag);
}
a[now].tag = INF;
}
}
void change (int now, int l, int r, int L, int R, int x)
{
if(l == L && r == R)
{
a[now].tag = Min(a[now].tag, x);
a[now].min = Min(a[now].min, x);
return ;
}
pushdown(now, l, r);
int mid = (l + r) >> 1;
if(R <= mid)
{
change(now << 1, l, mid, L, R, x);
}
else if(mid + 1 <= L)
{
change(now << 1 | 1, mid + 1, r, L, R, x);
}
else
{
change(now << 1, l, mid, L, mid, x);
change(now << 1 | 1, mid + 1, r, mid + 1, R, x);
}
a[now].min = Min(a[now << 1].min, a[now << 1 | 1].min);
}
int query (int now, int l, int r, int L, int R)
{
if(l == L && r == R)
{
return a[now].min;
}
pushdown(now, l, r);
int mid = (l + r) >> 1;
if(R <= mid)
{
return query(now << 1, l, mid, L, R);
}
else if(mid + 1 <= L)
{
return query(now << 1 | 1, mid + 1, r, L, R);
}
else
{
int A = query(now << 1, l, mid, L, mid);
int B = query(now << 1 | 1, mid + 1, r, mid + 1, R);
return Min(A, B);
}
}
int lca (int x, int y)
{
if(dep[x] < dep[y])
{
int t = x;
x = y;
y = t;
}
for(int i = 19;i >= 0; i--)
{
if(f[x][i] && dep[f[x][i]] >= dep[y])
{
x = f[x][i];
}
}
if(x == y)
{
return x;
}
for(int i = 19;i >= 0; i--)
{
if(f[x][i] && f[y][i] && f[x][i] != f[y][i])
{
x = f[x][i];
y = f[y][i];
}
}
return f[x][0];
}
void work (int x, int y, int c)
{
int LCA = lca(x, y);
int now = query(1, 1, n, number[LCA], number[LCA]);
while(top[x] != top[y])
{
if(dep[top[x]] < dep[top[y]])
{
int t = x;
x = y;
y = t;
}
if(top[x] == LCA)
{
if(top[x] != x)
{
change(1, 1, n, number[top[x]] + 1, number[x], c);
}
}
else
{
change(1, 1, n, number[top[x]], number[x], c);
}
x = f[top[x]][0];
}
if(dep[x] > dep[y])
{
int t = x;
x = y;
y = t;
}
if(x != y)
{
if(x == LCA)
{
change(1, 1, n, number[x] + 1, number[y], c);
}
else
{
change(1, 1, n, number[x], number[y], c);
}
}
}
int main ()
{
scanf("%d %d", &n, &m);
for(int i = 1;i < n; i++)
{
int x = 0, y = 0;
scanf("%d %d", &x, &y);
ins(x, y);
ins(y, x);
}
int root = 1;
dep[root] = 1;
dfs1(root);
top[root] = root;
for(int j = 1;j <= 19; j++)
{
for(int i = 1;i <= n; i++)
{
f[i][j] = f[f[i][j - 1]][j - 1];
}
}
dfs2(root);
build(1, 1, n);
for(int i = 1;i <= m; i++)
{
int x = 0, y = 0, c = 0;
scanf("%d %d %d", &x, &y, &c);
work(x, y, c);
}
for(int i = 2;i <= n; i++)
{
Ans[bh[i]] = query(1, 1, n, number[i], number[i]);
}
for(int i = 1;i < n; i++)
{
printf("%d\n", Ans[i] != 2147483647 ? Ans[i] : -1);
}
return 0;
}
|