如果沒有年齡區間
畫圖發現ans=\(\sum_{i=1}^n dis_i + n * dis_u - 2 * \sum_{i=1}^{n} dis_{lca(i, u)}\)

對\(\sum_{i=1}^{n} dis_{lca(i, u)}\)用樹鏈剖分，對於每個點，都向上走到根，記錄每條路經過次數，詢問時從u向上跳，每次加邊權*覆蓋次數即可

現在有年齡區間，加個前綴和，計算點權在[L,R]內的點到點u的距離，用主席樹

然而主席樹怎麽pushdown，加上標記永久化

# include <bits/stdc++.h>
# define IL inline
# define RG register
# define Fill(a, b) memset(a, b, sizeof(a))
using namespace std;
typedef long long ll;
const int _(3e6 + 10), __(1e7 + 10);

IL ll Read(){
    RG char c = getchar(); RG ll x = 0, z = 1;
    for(; c < '0' || c > '9'; c = getchar()) z = c == '-' ? -1 : 1;
    for(; c >= '0' && c <= '9'; c = getchar()) x = (x << 1) + (x << 3) + (c ^ 48);
    return x * z;
}

int n, m, Q, A, id[_], o[_];
int fst[_], nxt[_], to[_], w[_], size[_], fa[_], dfn[_], top[_], cnt, son[_], pos[_];
int rt[__], ls[__], rs[__], cov[__];
ll dis[_], sdis[_], sum[__];

IL bool Cmp(RG int x, RG int y){  return o[x] < o[y];  }

IL void Add(RG int u, RG int v, RG int f){  w[cnt] = f; to[cnt] = v; nxt[cnt] = fst[u]; fst[u] = cnt++;  }

IL void Dfs1(RG int u){
    size[u] = 1;
    for(RG int e = fst[u]; e != -1; e = nxt[e]){
        if(size[to[e]]) continue;
        dis[to[e]] = dis[u] + w[e]; fa[to[e]] = u;
        Dfs1(to[e]);
        size[u] += size[to[e]];
        if(size[to[e]] > size[son[u]]) son[u] = to[e];
    }
}

IL void Dfs2(RG int u, RG int Top){
    dfn[u] = ++cnt; top[u] = Top; pos[cnt] = u;
    if(son[u]) Dfs2(son[u], Top);
    for(RG int e = fst[u]; e != -1; e = nxt[e])
        if(!dfn[to[e]]) Dfs2(to[e], to[e]);
}

IL void Build(RG int &x, RG int l, RG int r){
    x = ++cnt;
    if(l == r) return;
    RG int mid = (l + r) >> 1;
    Build(ls[x], l, mid); Build(rs[x], mid + 1, r);
}

IL void Modify(RG int &x, RG int l, RG int r, RG int L, RG int R){
    sum[++cnt] = sum[x]; ls[cnt] = ls[x]; rs[cnt] = rs[x]; cov[cnt] = cov[x]; x = cnt;
    sum[x] += dis[pos[R]] - dis[fa[pos[L]]];
    if(L <= l && R >= r){  cov[x]++; return;  }
    RG int mid = (l + r) >> 1;
    if(R <= mid) Modify(ls[x], l, mid, L, R);
    else if(L > mid) Modify(rs[x], mid + 1, r, L, R);
    else Modify(ls[x], l, mid, L, mid), Modify(rs[x], mid + 1, r, mid + 1, R);
}

IL ll Query(RG int x, RG int ad, RG int l, RG int r, RG int L, RG int R){
    if(L <= l && R >= r) return sum[x] + 1LL * ad * (dis[pos[R]] - dis[fa[pos[L]]]);
    RG int mid = (l + r) >> 1;
    if(R <= mid) return Query(ls[x], ad + cov[x], l, mid, L, R);
    if(L > mid) return Query(rs[x], ad + cov[x], mid + 1, r, L, R);
    return Query(ls[x], ad + cov[x], l, mid, L, mid) + Query(rs[x], ad + cov[x], mid + 1, r, mid + 1, R);
}

IL ll Calc(RG int u, RG int i){
    RG ll ans = 0;
    while(top[u] ^ 1) ans += Query(rt[i], 0, 1, n, dfn[top[u]], dfn[u]), u = fa[top[u]];
    ans += Query(rt[i], 0, 1, n, 1, dfn[u]);
    return ans;
}

int main(RG int argc, RG char* argv[]){
    n = Read(); Q = Read(); A = Read();
    for(RG int i = 1; i <= n; ++i) o[i] = Read(), id[i] = i, fst[i] = -1;
    sort(id + 1, id + n + 1, Cmp); sort(o + 1, o + n + 1);
    for(RG int i = 1, aa, b, c; i < n; ++i) aa = Read(), b = Read(), c = Read(), Add(aa, b, c), Add(b, aa, c);
    Dfs1(1); cnt = 0; Dfs2(1, 1); cnt = 0; Build(rt[0], 1, n);
    for(RG int i = 1; i <= n; ++i){
        RG int u = id[i]; rt[i] = rt[i - 1];
        sdis[i] = sdis[i - 1] + dis[u];
        while(top[u] ^ 1) Modify(rt[i], 1, n, dfn[top[u]], dfn[u]), u = fa[top[u]];
        Modify(rt[i], 1, n, 1, dfn[u]);
    }
    for(RG ll L, R, u, a, b, ans = 0; Q; --Q){
        u = Read(); a = Read(); b = Read();
        L = min((a + ans) % A, (b + ans) % A);
        R = max((a + ans) % A, (b + ans) % A);
        L = lower_bound(o + 1, o + n + 1, L) - o;
        R = lower_bound(o + 1, o + n + 1, R + 1) - o - 1;
        ans = 1LL * (R - L + 1) * dis[u] + sdis[R] - sdis[L - 1] - 2LL * (Calc(u, R) - Calc(u, L - 1));
        printf("%lld\n", ans);
    }
    return 0;
}
 

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