제출 #47707

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
47707		square1001	Fireworks (APIO16_fireworks)	C++14	55 / 100	2070 ms	34452 KiB

fireworks

#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;
// Time complexity: possibly O(N+M log(N+M))
int N, M, p[300009], c[300009], id[300009]; vector<int> g[300009]; vector<long long> v[300009];
int main() {
	cin.tie(0);
	ios_base::sync_with_stdio(false);
	cin >> N >> M;
	long long sum = 0;
	for (int i = 1; i < N + M; i++) {
		cin >> p[i] >> c[i];
		g[--p[i]].push_back(i);
		sum += c[i];
		if (i >= N) {
			v[i - N].push_back(c[i]);
			v[i - N].push_back(c[i]);
			id[i] = i - N;
		}
	}
	for (int i = N - 1; i >= 0; i--) {
		int mx = 0;
		for (int j : g[i]) {
			if (mx < v[id[j]].size()) {
				mx = v[id[j]].size();
				id[i] = id[j];
			}
		}
		vector<int> dv = { 0, (int)v[id[i]].size() };
		for (int j : g[i]) {
			if (id[j] != id[i]) {
				v[id[i]].insert(v[id[i]].end(), v[id[j]].begin(), v[id[j]].end());
				dv.push_back(v[id[i]].size());
			}
		}
		int ds = dv.size() - 1;
		for (int j = 1; j < ds; j *= 2) {
			for (int k = 0; k < ds; k += j * 2) {
				if (k + j * 2 <= ds) {
					vector<long long> tmp(dv[k + j * 2] - dv[k]);
					merge(v[id[i]].begin() + dv[k], v[id[i]].begin() + dv[k + j], v[id[i]].begin() + dv[k + j], v[id[i]].begin() + dv[k + j * 2], tmp.begin());
					copy(tmp.begin(), tmp.end(), v[id[i]].begin() + dv[k]);
				}
				else if (k + j < ds) {
					vector<long long> tmp(dv[ds] - dv[k]);
					merge(v[id[i]].begin() + dv[k], v[id[i]].begin() + dv[k + j], v[id[i]].begin() + dv[k + j], v[id[i]].end(), tmp.begin());
					copy(tmp.begin(), tmp.end(), v[id[i]].begin() + dv[k]);
				}
			}
		}
		v[id[i]].resize(v[id[i]].size() - g[i].size() + 1);
		v[id[i]][v[id[i]].size() - 1] += c[i];
		v[id[i]][v[id[i]].size() - 2] += c[i];
	}
	for (int i = 0; i < v[id[0]].size(); i++) {
		sum -= (v[id[0]][i] - (i == 0 ? 0 : v[id[0]][i - 1])) * (v[id[0]].size() - i - 1);
	}
	cout << sum << '\n';
	return 0;
}

컴파일 시 표준 에러 (stderr) 메시지

fireworks.cpp: In function 'int main()':
fireworks.cpp:25:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    if (mx < v[id[j]].size()) {
        ~~~^~~~~~~~~~~~~~~~~
fireworks.cpp:56:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 0; i < v[id[0]].size(); i++) {
                  ~~^~~~~~~~~~~~~~~~~

• Subtask 1: 7 / 7
• Subtask 2: 19 / 19
• Subtask 3: 29 / 29
• Subtask 4: 0 / 45