Submission #1222597

#	Time	Username	Problem	Language	Result	Execution time	Memory
1222597		vladilius	Saveit (IOI10_saveit)	C++20	50 / 100	49 ms	5800 KiB

encoder

#include "grader.h"
#include "encoder.h"
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using pii = pair<int, int>;
#define pb push_back
#define ff first
#define ss second

void encode(int n, int h, int m, int* a, int* b){
    vector<int> g[n];
    for (int i = 0; i < m; i++){
        g[a[i]].pb(b[i]);
        g[b[i]].pb(a[i]);
    }
    
    vector<int> p(n, -1); p[0] = 0;
    queue<int> q; q.push(0);
    while (!q.empty()){
        int v = q.front(); q.pop();
        for (int i: g[v]){
            if (p[i] == -1){
                p[i] = v;
                q.push(i);
            }
        }
    }
    
    for (int i = 1; i < n; i++){
        for (int j = 0; j < 10; j++){
            encode_bit((p[i] >> j) & 1);
        }
    }
    
    for (int i = 1; i < h; i++){
        vector<int> dist(n, 1e9); dist[i] = 0;
        q.push(i);
        while (!q.empty()){
            int v = q.front(); q.pop();
            for (int u: g[v]){
                if (dist[u] == 1e9){
                    dist[u] = dist[v] + 1;
                    q.push(u);
                }
            }
        }
        
        for (int j = 0; j < 10; j++){
            encode_bit((dist[0] >> j) & 1);
        }
        
        for (int i = 1; i < n; i++){
            int x = dist[i] - dist[p[i]]; x++;
            encode_bit((x >> 0) & 1);
            encode_bit((x >> 1) & 1);
        }
    }
}

decoder

#include "grader.h"
#include "encoder.h"
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using pii = pair<int, int>;
#define pb push_back
#define ff first
#define ss second

void decode(int n, int h){
    vector<int> p(n), g[n];
    for (int i = 1; i < n; i++){
        for (int j = 0; j < 10; j++){
            bool x = decode_bit();
            if (x){
                p[i] += (1 << j);
            }
        }
    }
    
    for (int i = 1; i < n; i++){
        g[p[i]].pb(i);
    }
    vector<int> order, D(n);
    function<void(int)> dfs = [&](int v){
        if (v){
            order.pb(v);
            D[v] = D[p[v]] + 1;
        }
    
        for (int i: g[v]){
            if (i != p[v]){
                dfs(i);
            }
        }
    };
    dfs(0);
    
    for (int i = 0; i < n; i++){
        hops(0, i, D[i]);
    }
    
    for (int i = 1; i < h; i++){
        vector<int> d(n);
        for (int j = 0; j < 10; j++){
            bool x = decode_bit();
            if (x){
                d[0] += (1 << j);
            }
        }
        
        vector<int> V(n);
        
        for (int j = 1; j < n; j++){
            for (int k = 0; k < 2; k++){
                bool x = decode_bit();
                if (x){
                    V[j] += (1 << k);
                }
            }
        }
        
        for (int j: order){
            d[j] = d[p[j]] + V[j] - 1;
        }
        
        for (int j = 0; j < n; j++){
            hops(i, j, d[j]);
        }
    }
}

• Subtask 1: 25 / 25
• Subtask 2: 25 / 25
• Subtask 3: 0 / 25
• Subtask 4: 0 / 25