oj.uz

답안 #875144

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
875144 2023-11-18T17:45:52 Z MinaRagy06 Arboras (RMI20_arboras) C++17
0 / 100
 37 ms 3668 KB 
#include <bits/stdc++.h>
using namespace std;
#define ll long long

const int mod = 1e9 + 7;
struct mint {
	int v = 0;
	mint() {}
	mint(int x) {v = x;}
	mint& operator+=(mint b) {
		if ((v += b.v) >= mod) {
			v -= mod;
		}
		return *this;
	}
	mint& operator-=(mint b) {
		if ((v -= b.v) < 0) {
			v += mod;
		}
		return *this;
	}
	friend mint operator+(mint a, mint b) {
		return a += b;
	}
	friend mint operator-(mint a, mint b) {
		return a -= b;
	}
	friend bool operator>(mint a, mint b) {
		return a.v > b.v;
	}
	friend bool operator<(mint a, mint b) {
		return b > a;
	}
	friend ostream& operator<<(ostream &os, mint a) {
		return os << a.v;
	}
};
int main() {
	ios_base::sync_with_stdio(0), cin.tie(0);
	int n;
	cin >> n;
	int p[n]{};
	for (int i = 1; i < n; i++) {
		cin >> p[i];
	}
	int d[n]{};
	for (int i = 1; i < n; i++) {
		cin >> d[i];
	}
	pair<mint, int> dp[n][2];
	for (int i = 0; i < n; i++) {
		dp[i][0] = dp[i][1] = {0, -1};
	}
	mint ans = 0;
	for (int i = n - 1; i > 0; i--) {
		if (dp[i][0].first + d[i] > dp[p[i]][1].first) {
			dp[p[i]][1] = {dp[i][0].first + d[i], i};
			if (dp[p[i]][1] > dp[p[i]][0]) swap(dp[p[i]][0], dp[p[i]][1]);
		}
		ans += dp[i][0].first + dp[i][1].first;
	}
	ans += dp[0][0].first + dp[0][1].first;
	cout << (ans.v % mod + mod) % mod << '\n';
	int q;
	cin >> q;
	while (q--) {
		int i, v;
		cin >> i >> v;
		d[i] += v;
		d[i] %= mod;
		mint old = 0, cur = -1;
		while (old.v != cur.v && i != 0) {
			old = cur = dp[p[i]][0].first;
			if (dp[p[i]][0].second == i) {
				swap(dp[p[i]][0], dp[p[i]][1]);
			}
			if (dp[p[i]][1].second == i || dp[i][0].first + d[i] > dp[p[i]][1].first) {
				ans -= dp[p[i]][0].first + dp[p[i]][1].first;
				dp[p[i]][1] = {dp[i][0].first + d[i], i};
				if (dp[p[i]][1] > dp[p[i]][0]) {
					swap(dp[p[i]][0], dp[p[i]][1]);
				}
				cur = dp[p[i]][0].first;
				ans += dp[p[i]][0].first + dp[p[i]][1].first;
			}
			i = p[i];
		}
		cout << (ans.v % mod + mod) % mod << '\n';
	}
	return 0;
}

Subtask #1
0 / 11.0

# 결과 실행 시간 메모리 Grader output
1 Incorrect 1 ms 348 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #2
0 / 13.0

# 결과 실행 시간 메모리 Grader output
1 Incorrect 37 ms 3668 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #3
0 / 31.0

# 결과 실행 시간 메모리 Grader output
1 Incorrect 37 ms 3668 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #4
0 / 45.0

# 결과 실행 시간 메모리 Grader output
1 Incorrect 1 ms 348 KB Output isn't correct
2 Halted 0 ms 0 KB -