Submission #1321750

#	Time	Username	Problem	Language	Result	Execution time	Memory
1321750		benjaminkleyn	Migrations (IOI25_migrations)	C++20	30 / 100	31 ms	1448 KiB

migrations

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

int n;
int P[10000];
vector<int> g[10000];
int dist[10000] = {0};
void dfs(int u, int p = -1)
{
    if (p == -1) dist[u] = 0;
    for (int v : g[u]) if (v != p) {
        dist[v] = dist[u] + 1;
        dfs(v, u);
    }
}

int prev_a, prev_b;
int a, b;
void find_diameter()
{
    prev_a = a;
    prev_b = b;
    a = b = 0;
    dfs(0);
    for (int i = 0; i < n; i++)
        if (dist[i] > dist[a])
            a = i;

    // dfs(a);
    // for (int i = 0; i < n; i++)
    //     if (dist[i] > dist[b])
    //         b = i;
}

bool cancelled = false;
int send_message(int N, int i, int Pi)
{
    n = N;
    g[i].push_back(Pi);
    g[Pi].push_back(i);

    if (i >= N - 8) {
        find_diameter();
        if (a == i) {
            cancelled = true;
            return 0;
        }
        if (cancelled) {
            return 1;
        }
        int shift_amount = 2 * (N - 1 - i);
        return ((a >> shift_amount) & 0b11) + 1;
    }
    return 0;
}

pair<int, int> longest_path(vector<int> S)
{
    int N = S.size();
    int res = 0;
    for (int i = N - 1; i >= N - 8; i--) {
        if (S[i] == 0)
            return {0, i};
        int shift_amount = 2 * (N - 1 - i);
        res |= (S[i] - 1) << shift_amount;
    }
    return {0, res};
}

• Subtask 0: 0 / 0
• Subtask 1: 30 / 30
• Subtask 2: 0 / 70