Submission #946920

#	Time	Username	Problem	Language	Result	Execution time	Memory
946920		Esgeer	Race (IOI11_race)	C++17	100 / 100	425 ms	110424 KiB

race

#include <bits/stdc++.h>
using namespace std;
#include <ext/pb_ds/assoc_container.hpp>
#include <unistd.h>
using namespace __gnu_pbds;
template <class T>
using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
#ifndef Local
    #pragma GCC optimize("O3,unroll-loops")
#endif
//#define int long long
#define vi vector<int>
#define vvi vector<vi>
//#define pii pair<int, int>
#define vpi vector<pii>
#define vvpi vector<vpi>
#define vb vector<bool>
#define vvb vector<vb>
#define endl '\n'
#define sp << " " <<
#define F(i, s, n) for(int i = s; i < n; i++)
#define pb push_back
#define fi first
#define se second

#include "race.h"
 
typedef long long ll;
typedef pair<ll, ll> pii;
ll inf = 1e18;
int32_t h[200005][2];
int32_t l[200005];

#define pb push_back

#define f first
#define s second

const int maxn = 2e5 + 1;
vector<pii> adj[maxn];
map<ll, ll> info[maxn];
ll dist[maxn], sum[maxn];  // define these relative to root
int N, K;
ll ret;

void precomp(int u, int p, ll c, int h) {
	info[u][c] = h;
	sum[u] = c;
	dist[u] = h;
	for (auto n : adj[u]) {
		if (p == n.f) { continue; }
		precomp(n.f, u, c + n.s, h + 1);
	}
}

void small_to_large_merge(int u, int p) {
	ll target = K + 2 * sum[u];
	for (auto n : adj[u]) {
		if (n.f == p) { continue; }
		small_to_large_merge(n.f, u);
		if (info[n.f].size() > info[u].size()) { swap(info[n.f], info[u]); }
		for (auto i : info[n.f]) {
			if (info[u].find(target - i.f) != info[u].end()) {
				ret = min(ret, info[u][target - i.f] + i.s - 2 * dist[u]);
			}
		}
		for (auto i : info[n.f]) {
			if (info[u].find(i.f) == info[u].end()) {
				info[u].insert(i);
			} else {
				info[u][i.f] = min(info[u][i.f], i.s);
			}
		}
	}
}

int best_path(int n, int k, int edges[][2], int weights[]) {
	if (k == 1) { return 0; }
	N = n;
	K = k;
	ret = INT_MAX;
	for (int i = 0; i < n - 1; i++) {
		int u = edges[i][0];
		int v = edges[i][1];
		adj[u].pb(pii(v, weights[i]));
		adj[v].pb(pii(u, weights[i]));
	}
	precomp(0, -1, 0, 0);
	small_to_large_merge(0, -1);
	return ret == INT_MAX ? -1 : ret;
}

/*void solve() {
    int32_t n, k;
    cin >> n >> k;

    F(i, 0, n-1) cin >> h[i][0] >> h[i][1];
    F(i, 0, n-1) cin >> l[i];

    cout << best_path(n, k, h, l) << endl;
}
 
void setIO() {
    ios_base::sync_with_stdio(0); cin.tie(0);
    #ifdef Local
        freopen("local.in", "r", stdin);
        freopen("local.out", "w", stdout);
    #else 
        // freopen("disrupt.in","r",stdin);
        // freopen("disrupt.out","w",stdout);
    #endif
}
signed main() {
    setIO();
    int t = 1;
    //cin >> t;
    while(t--) solve();
}*/

• Subtask 1: 9 / 9
• Subtask 2: 12 / 12
• Subtask 3: 22 / 22
• Subtask 4: 57 / 57