Submission #111463

#	Time	Username	Problem	Language	Result	Execution time	Memory
111463		ecasdqina	Fireworks (APIO16_fireworks)	C++14	19 / 100	40 ms	1144 KiB

fireworks

#include <bits/stdc++.h>
using namespace std::literals::string_literals;
using i64 = long long;
using std::cout;
using std::endl;
using std::cin;

template<typename T>
std::vector<T> make_v(size_t a){return std::vector<T>(a);}

template<typename T,typename... Ts>
auto make_v(size_t a,Ts... ts){
  return std::vector<decltype(make_v<T>(ts...))>(a,make_v<T>(ts...));
}

int main() {
	int n, m; scanf("%d%d", &n, &m);
	std::vector<int> leaf(m);
	std::vector<std::vector<std::pair<int, i64>>> g(n + m); n += m;
	for(int i = 1; i < n; i++) {
		int a; i64 b; scanf("%d%lld", &a, &b);
		
	//	g[i].push_back({a - 1, b});
		g[a - 1].push_back({i, b});
	}
	
	std::vector<i64> dist(n, 0);
	std::function<void (int, int, i64)> dfs = [&](int v, int par, i64 ari) {
		dist[v] = ari;
		for(auto e: g[v]) {
			if(e.first == par) continue;
			dfs(e.first, v, ari + e.second);
		}
	};
	dfs(0, -1, 0);
	for(auto v: dist) assert(v <= 300);
	
	assert(n <= 300);
	
	i64 ans = 1LL << 60;
	auto dp = make_v<i64>(n, 301);
	for(int i = 0; i < dp.size(); i++) for(int j = 0; j < dp[i].size(); j++) dp[i][j] = 1LL << 60;
	std::function<void (int)> solve = [&](int v) {
		if(v > n - m - 1) {
			dp[v][0] = 0;
			return;
		}
		
		for(auto e: g[v]) solve(e.first);
		for(int i = 0; i < dp[v].size(); i++) {
			i64 tmp = 0;
			for(auto e: g[v]) {
				i64 mi = 1LL << 60;
				for(int j = 0; j < dp[e.first].size(); j++) {
					i64 diff = i - (j + e.second);
					if(e.second + diff < 0) continue;
					mi = std::min(mi, dp[e.first][j] + std::abs(diff));
				}
				tmp += mi;
			}
			dp[v][i] = tmp;
		}
	};
	solve(0);
	
	for(auto v: dp[0]) ans = std::min(ans, v);
	printf("%lld\n", ans);
	return 0;
}

Compilation message (stderr)

fireworks.cpp: In function 'int main()':
fireworks.cpp:42:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0; i < dp.size(); i++) for(int j = 0; j < dp[i].size(); j++) dp[i][j] = 1LL << 60;
                 ~~^~~~~~~~~~~
fireworks.cpp:42:54: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0; i < dp.size(); i++) for(int j = 0; j < dp[i].size(); j++) dp[i][j] = 1LL << 60;
                                                    ~~^~~~~~~~~~~~~~
fireworks.cpp: In lambda function:
fireworks.cpp:50:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int i = 0; i < dp[v].size(); i++) {
                  ~~^~~~~~~~~~~~~~
fireworks.cpp:54:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int j = 0; j < dp[e.first].size(); j++) {
                    ~~^~~~~~~~~~~~~~~~~~~~
fireworks.cpp: In function 'int main()':
fireworks.cpp:17:17: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  int n, m; scanf("%d%d", &n, &m);
            ~~~~~^~~~~~~~~~~~~~~~
fireworks.cpp:21:22: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   int a; i64 b; scanf("%d%lld", &a, &b);
                 ~~~~~^~~~~~~~~~~~~~~~~~

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