122 lines
3.5 KiB
C++
122 lines
3.5 KiB
C++
#include<bits/stdc++.h>
|
|
const int mod = 201314;
|
|
using namespace std;
|
|
int n, m;
|
|
vector<int> chi[50005];
|
|
int fa[50005];
|
|
int cnt[50005];
|
|
int son[50005];
|
|
int top[50005];
|
|
int dep[50005];
|
|
int dfn[50005];
|
|
int nowdfn;
|
|
pair<int, int> query[100005];
|
|
struct SEG{
|
|
int num[400005], lt[400005];
|
|
void pu(int now) {num[now] = (1ll * num[now * 2] + num[now * 2 + 1]) % mod;}
|
|
void pd(int now, int nl, int nr) {
|
|
int nmid = (nl + nr) >> 1;
|
|
num[now * 2] = (num[now * 2] + 1ll * (nmid - nl + 1) * lt[now]) % mod;
|
|
num[now * 2 + 1] = (num[now * 2 + 1] + 1ll * (nr - nmid) * lt[now]) % mod;
|
|
lt[now * 2] = (lt[now * 2] + lt[now]) % mod;
|
|
lt[now * 2 + 1] = (lt[now * 2 + 1] + lt[now]) % mod;
|
|
lt[now] = 0;
|
|
}
|
|
void add(int now, int nl, int nr, int l, int r, int nn) {
|
|
if(nl > r || nr < l) return;
|
|
if(l <= nl && nr <= r) {
|
|
num[now] = (num[now] + 1ll * (nr - nl + 1) * nn) % mod;
|
|
lt[now] = (lt[now] + 1ll * nn) % mod;
|
|
return;
|
|
}
|
|
int nmid = (nl + nr) >> 1;
|
|
pd(now, nl, nr);
|
|
add(now * 2, nl, nmid, l, r, nn);
|
|
add(now * 2 + 1, nmid + 1, nr, l, r, nn);
|
|
pu(now);
|
|
}
|
|
int query(int now, int nl, int nr, int l, int r) {
|
|
if(nl > r || nr < l) return 0;
|
|
if(l <= nl && nr <= r) {
|
|
return num[now];
|
|
}
|
|
int nmid = (nl + nr) >> 1;
|
|
pd(now, nl, nr);
|
|
return (1ll * query(now * 2, nl, nmid, l, r) + query(now * 2 + 1, nmid + 1, nr, l, r)) % mod;
|
|
}
|
|
}seg;
|
|
void dfs1(int now) {
|
|
cnt[now] = 1;
|
|
for(int i : chi[now]) {
|
|
dep[i] = dep[now] + 1;
|
|
dfs1(i);
|
|
cnt[now] += cnt[i];
|
|
if(cnt[son[now]] < cnt[i]) son[now] = i;
|
|
}
|
|
}
|
|
void dfs2(int now, int from) {
|
|
top[now] = from;
|
|
dfn[now] = ++nowdfn;
|
|
if(son[now]) dfs2(son[now], from);
|
|
for(int i : chi[now]) {
|
|
if(i == son[now]) continue;
|
|
dfs2(i, i);
|
|
}
|
|
}
|
|
void addpath(int a, int b = 1) {
|
|
while(top[a] != top[b]) {
|
|
if(dep[top[a]] < dep[top[b]]) swap(a, b);
|
|
seg.add(1, 1, n, dfn[top[a]], dfn[a], 1);
|
|
a = fa[top[a]];
|
|
}
|
|
if(dep[a] < dep[b]) swap(a, b);
|
|
seg.add(1, 1, n, dfn[b], dfn[a], 1);
|
|
}
|
|
int querypath(int a, int b = 1) {
|
|
int ans = 0;
|
|
while(top[a] != top[b]) {
|
|
if(dep[top[a]] < dep[top[b]]) swap(a, b);
|
|
ans = (ans + 1ll * seg.query(1, 1, n, dfn[top[a]], dfn[a])) % mod;
|
|
a = fa[top[a]];
|
|
}
|
|
if(dep[a] < dep[b]) swap(a, b);
|
|
return (ans + 1ll * seg.query(1, 1, n, dfn[b], dfn[a])) % mod;
|
|
}
|
|
int sx[100005];
|
|
int ans[100005];
|
|
int main() {
|
|
scanf("%d%d", &n, &m);
|
|
for(int i = 2; i <= n; ++i) {
|
|
scanf("%d", &fa[i]);
|
|
fa[i]++;
|
|
chi[fa[i]].push_back(i);
|
|
}
|
|
dfs1(1);
|
|
dfs2(1, 1);
|
|
for(int i = 1, l, r, z; i <= m; ++i) {
|
|
scanf("%d%d%d", &l, &r, &z);
|
|
l++, r++, z++;
|
|
sx[i] = i;
|
|
sx[i + m] = i + m;
|
|
query[2 * i - 1] = {l - 1, z};
|
|
query[2 * i] = {r, z};
|
|
}
|
|
sort(sx + 1, sx + 2 * m + 1, [](int x, int y){return query[x] < query[y];});
|
|
int cur = 0;
|
|
for(int i = 1; i <= 2 * m; ++i) {
|
|
int u = query[sx[i]].first;
|
|
int w = query[sx[i]].second;
|
|
while(cur < u) {
|
|
++cur;
|
|
addpath(cur);
|
|
}
|
|
ans[sx[i]] = querypath(w);
|
|
}
|
|
for(int i = 1; i <= m; ++i) {
|
|
printf("%d\n", (ans[2 * i] - ans[2 * i - 1] + mod) % mod);
|
|
}
|
|
return 0;
|
|
}
|
|
/*
|
|
从根到 [l, r] 中每个点的路径上的点均 + 1，最否求 z 到根的路径权值和
|
|
*/ |