Submission #1200177

#	Time	Username	Problem	Language	Result	Execution time	Memory
1200177		thieunguyenhuy	Fireworks (APIO16_fireworks)	C++20	7 / 100	1 ms	784 KiB

fireworks

#include <bits/stdc++.h>
using namespace std;

#define POPCOUNT(n) (__builtin_popcountll((n)))
#define CLZ(n) (__builtin_clzll((n)))
#define CTZ(n) (__builtin_ctzll((n)))
#define LOG(n) (63 - __builtin_clzll((n)))
#define BIT(n, i) (((n) >> (i)) & 1ll)
#define MASK(i) (1ll << (i))
#define FLIP(n, i) ((n) ^ (1ll << (i)))
#define ON(n, i) ((n) | MASK(i))
#define OFF(n, i) ((n) & ~MASK(i))

#define Int __int128
#define fi first
#define se second

typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<long long, long long> pll;
typedef pair<long long, int> pli;
typedef pair<int, long long> pil;
typedef vector<pair<int, int>> vii;
typedef vector<pair<long long, long long>> vll;
typedef vector<pair<long long, int>> vli;
typedef vector<pair<int, long long>> vil;

template <class T1, class T2> bool maximize(T1 &x, T2 y) {
    if (x < y) {
        x = y;
        return true;
    }
    return false;
}
template <class T1, class T2> bool minimize(T1 &x, T2 y) {
    if (x > y) {
        x = y;
        return true;
    }
    return false;
}

template <class T> void remove_duplicate(vector<T> &ve) {
    sort (ve.begin(), ve.end());
    ve.resize(unique(ve.begin(), ve.end()) - ve.begin());
}

mt19937_64 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
template <class T1, class T2> T1 random(T1 l, T2 r) {
    return uniform_int_distribution<T1>(l, r)(rng);
}
template <class T> T random(T r) {
    return rng() % r;
}

const int N = 5000 + 5;
const int MOD = 1e9 + 7;
const int inf = 1e9;
const long long INF = 1e18;

int n, m;
int par[N], c[N];
ll dist[N], dp[N][N];
vii adj[N];
vector<int> leaf[N];

void prepare(int u) {
	if (adj[u].empty()) leaf[u].emplace_back(u);
	
	for (auto [v, w] : adj[u]) {
		dist[v] = dist[u] + w;
		prepare(v);
		for (auto &x : leaf[v]) leaf[u].emplace_back(x);
	}
}

void dfs(int u) {
	for (auto [v, w] : adj[u]) {
		dfs(v);
	}

	for (auto x : leaf[u]) {
		for (auto [v, w] : adj[u]) {
			ll bestY = INF;
			for (auto &y : leaf[v]) {
				// w - dist[y] + dist[x]
				if (w - dist[y] + dist[x] >= 0)
					minimize(bestY, dp[v][y] + abs(dist[x] - dist[y]));
			}
			dp[u][x] += bestY;
		}
		// cerr << u << ' ' << x << ' ' << dp[u][x] << '\n';
	}
}

signed main() {
    ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);

    cin >> n >> m;

    for (int i = 2; i <= n + m; ++i) {
    	cin >> par[i] >> c[i];
    	adj[par[i]].emplace_back(i, c[i]);
    }

    // cerr << '\n';
    // for (int i = 2; i <= n + m; ++i)
    // 	cerr << par[i] << ' ' << i << ' ' << c[i] << '\n';
    // cerr << '\n';

    prepare(1);
    dfs(1);

    ll ans = INF;
    for (auto &x : leaf[1]) minimize(ans, dp[1][x]);
    cout << ans << '\n';
    return 0;
}

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