InternBootcamp/internbootcamp/bootcamp/eonchangingtree/eonchangingtree.py
2025-05-23 15:27:15 +08:00

270 lines
8.4 KiB
Python
Executable file

"""#
### 谜题描述
You are given a rooted tree consisting of n vertices numbered from 1 to n. The root of the tree is a vertex number 1.
Initially all vertices contain number 0. Then come q queries, each query has one of the two types:
* The format of the query: 1 v x k. In response to the query, you need to add to the number at vertex v number x; to the numbers at the descendants of vertex v at distance 1, add x - k; and so on, to the numbers written in the descendants of vertex v at distance i, you need to add x - (i·k). The distance between two vertices is the number of edges in the shortest path between these vertices.
* The format of the query: 2 v. In reply to the query you should print the number written in vertex v modulo 1000000007 (109 + 7).
Process the queries given in the input.
Input
The first line contains integer n (1 ≤ n ≤ 3·105) — the number of vertices in the tree. The second line contains n - 1 integers p2, p3, ... pn (1 ≤ pi < i), where pi is the number of the vertex that is the parent of vertex i in the tree.
The third line contains integer q (1 ≤ q ≤ 3·105) — the number of queries. Next q lines contain the queries, one per line. The first number in the line is type. It represents the type of the query. If type = 1, then next follow space-separated integers v, x, k (1 ≤ v ≤ n; 0 ≤ x < 109 + 7; 0 ≤ k < 109 + 7). If type = 2, then next follows integer v (1 ≤ v ≤ n) — the vertex where you need to find the value of the number.
Output
For each query of the second type print on a single line the number written in the vertex from the query. Print the number modulo 1000000007 (109 + 7).
Examples
Input
3
1 1
3
1 1 2 1
2 1
2 2
Output
2
1
Note
You can read about a rooted tree here: http://en.wikipedia.org/wiki/Tree_(graph_theory).
Here is a reference code to solve this task. You can use this to help you genereate cases or validate the solution.
```python
#include <bits/stdc++.h>
const int N = 300200;
using namespace std;
int n;
int tim;
int tin[N];
int tout[N];
int dep[N];
int mod = 1e9 + 7;
pair<int, int> t[4 * N];
vector<int> v[N];
void dfs(int x, int g) {
tin[x] = tout[x] = ++tim;
dep[tin[x]] = g;
for (auto y : v[x]) {
dfs(y, g - 1);
tout[x] = tout[y];
}
}
void push(int x) {
t[x * 2].first += t[x].first;
t[x * 2].second += t[x].second;
t[x * 2 + 1].first += t[x].first;
t[x * 2 + 1].second += t[x].second;
t[x * 2].first %= mod;
t[x * 2].second %= mod;
t[x * 2 + 1].first %= mod;
t[x * 2 + 1].second %= mod;
t[x].first = t[x].second = 0;
}
void upd(int x, int l, int r, int tl, int tr, int f1, int f2) {
if (tl > tr) return;
if (l == tl && r == tr) {
t[x].first = (t[x].first + f1) % mod;
t[x].second = (t[x].second + f2) % mod;
return;
}
push(x);
int m = (l + r) / 2;
upd(x * 2, l, m, tl, min(m, tr), f1, f2);
upd(x * 2 + 1, m + 1, r, max(m + 1, tl), tr, f1, f2);
}
int get(int x, int l, int r, int g) {
if (l == r) {
int ans = (1ll * t[x].second * dep[l]) % mod;
ans = (t[x].first + ans) % mod;
return ans;
}
push(x);
int m = (l + r) / 2;
if (g <= m)
return get(x * 2, l, m, g);
else
return get(x * 2 + 1, m + 1, r, g);
}
int main() {
ios_base::sync_with_stdio(0);
scanf(\"%d\", &n);
for (int i = 2; i <= n; i++) {
int x;
scanf(\"%d\", &x);
v[x].push_back(i);
}
dfs(1, n);
int q;
scanf(\"%d\", &q);
for (int i = 1; i <= q; i++) {
int t, v, x, k;
scanf(\"%d\", &t);
if (t == 1) {
scanf(\"%d%d%d\", &v, &x, &k);
long long f = 1ll * x - 1ll * dep[tin[v]] * k;
f = f % mod + mod;
upd(1, 1, n, tin[v], tout[v], f % mod, k);
} else {
scanf(\"%d\", &v);
printf(\"%d\n\", get(1, 1, n, tin[v]));
}
}
}
```
请完成上述谜题的训练场环境类实现,包括所有必要的方法。
"""
from bootcamp import Basebootcamp
import random
import re
from bootcamp import Basebootcamp
mod = 10**9 + 7
def build_adj(parents, n):
adj = {i: [] for i in range(1, n+1)}
for i in range(2, n+1):
parent = parents[i-2]
adj[parent].append(i)
return adj
def dfs(x, parent_adj, tin, tout, dep, current_time, current_g):
current_time[0] += 1
tin[x] = current_time[0]
dep[tin[x]] = current_g
for child in parent_adj.get(x, []):
dfs(child, parent_adj, tin, tout, dep, current_time, current_g-1)
tout[x] = current_time[0]
def perform_dfs(n, parent_adj):
tin = [0] * (n + 1)
tout = [0] * (n + 1)
dep = [0] * (n + 2) # tin values are 1-based
current_time = [0]
dfs(1, parent_adj, tin, tout, dep, current_time, n)
return tin, tout, dep
def process_queries_for_identity(queries, n, tin_dict, tout_dict, dep_list):
a = [0] * (n + 2)
b = [0] * (n + 2)
expected_outputs = []
for query in queries:
if query['type'] == 1:
v = query['v']
x = query['x']
k = query['k']
tin_v = tin_dict[v]
tout_v = tout_dict[v]
f1 = (x - dep_list[tin_v] * k) % mod
f2 = k % mod
for u in range(1, n+1):
u_tin = tin_dict[u]
if tin_v <= u_tin <= tout_v:
a[u_tin] = (a[u_tin] + f1) % mod
b[u_tin] = (b[u_tin] + f2) % mod
else:
v = query['v']
u_tin = tin_dict[v]
res = (a[u_tin] + b[u_tin] * dep_list[u_tin]) % mod
expected_outputs.append(res)
return expected_outputs
class Eonchangingtreebootcamp(Basebootcamp):
def __init__(self, max_n=5, max_q=5):
self.max_n = max_n
self.max_q = max_q
def case_generator(self):
n = random.randint(1, self.max_n)
parents = []
if n > 1:
parents = [random.randint(1, i-1) for i in range(2, n+1)]
adj = build_adj(parents, n)
tin, tout, dep = perform_dfs(n, adj)
tin_dict = {x: tin[x] for x in range(1, n+1)}
tout_dict = {x: tout[x] for x in range(1, n+1)}
q = random.randint(1, self.max_q)
queries = []
for _ in range(q):
if random.random() < 0.3 or not any(q.get('type') == 2 for q in queries):
v = random.randint(1, n)
queries.append({'type': 2, 'v': v})
else:
v = random.randint(1, n)
x = random.randint(0, mod-1)
k = random.randint(0, mod-1)
queries.append({'type': 1, 'v': v, 'x': x, 'k': k})
expected_outputs = process_queries_for_identity(queries, n, tin_dict, tout_dict, dep)
new_queries = []
output_idx = 0
for q in queries:
if q['type'] == 2:
new_q = q.copy()
new_q['expected'] = expected_outputs[output_idx]
new_queries.append(new_q)
output_idx += 1
else:
new_queries.append(q)
return {
'n': n,
'parents': parents,
'queries': new_queries,
'tin_dict': tin_dict,
'tout_dict': tout_dict,
'dep_list': dep
}
@staticmethod
def prompt_func(question_case):
input_lines = [
str(question_case['n']),
' '.join(map(str, question_case['parents'])) if question_case['n'] > 1 else '',
str(len(question_case['queries']))
]
for q in question_case['queries']:
if q['type'] == 1:
input_lines.append(f"1 {q['v']} {q['x']} {q['k']}")
else:
input_lines.append(f"2 {q['v']}")
input_str = '\n'.join(input_lines)
return f"""你正在解决一个树处理问题。处理所有查询并将每个类型2的答案放在[answer]和[/answer]之间。输入数据如下:
{input_str}
规则:
1. 类型1查询为节点v及其后代按距离加值。
2. 类型2查询输出节点值模10^9+7的结果。
答案格式示例:
[answer]结果1[/answer]
[answer]结果2[/answer]"""
@staticmethod
def extract_output(output):
matches = re.findall(r'\[answer\]\s*(\d+)\s*\[/answer\]', output)
try:
return [int(m) % mod for m in matches] if matches else None
except:
return None
@classmethod
def _verify_correction(cls, solution, identity):
expected = [q['expected'] for q in identity['queries'] if q['type'] == 2]
return solution == expected if solution else False