Submission #1016111

#	Time	Username	Problem	Language	Result	Execution time	Memory
1016111		amine_aroua	Magic Show (APIO24_show)	C++17	0 / 100	2 ms	1084 KiB

Alice

#include <bits/stdc++.h>
#include "Alice.h"
using namespace std;
// you may define some global variables, but it does not work if you try to transfer any information from function Alice() to function Bob() through these variables.
// you had better not use the same global variables in function Alice() and in function Bob().
const int N = 5000;
const int B = 1000;
const int CNT = (N - B)/25;
vector<int> bits[25];

#define myrand( l , r , rng) uniform_int_distribution<int>(l , r)(rng)
std::vector<std::pair<int,int>> Alice(){
    mt19937 rng1(1313);
    mt19937 rng2(chrono::steady_clock::now().time_since_epoch().count());
    vector<int> perm;
    vector<pair<int ,int>> vp;
    for(int i = 1 ; i <= N ; i++)
    {
        perm.push_back(i);
    }
    shuffle(perm.begin() , perm.end() , rng1);
    vector<int> tree = {perm[0]};
    for(int i = 1 ; i < B ; i++)
    {
        vp.push_back({perm[i] , perm[myrand(0 , (int)tree.size() - 1 , rng2)]});
        tree.push_back(perm[i]);
    }
    assert((int)tree.size() == B);
    for(int i = 0 ; i < 25 ; i++)
    {
        for(int j = B + i * CNT ; j < B + (i + 1) * CNT ; j++)
        {
            bits[i].push_back(perm[j]);
        }
    }
    long long X = setN(N);
    vector<int> all;
    for(int i = 0 ; i < 25 ; i++)
    {
        if((1<<i) & X)
        {
            for(auto j : bits[i])
            {
                vp.push_back({tree[myrand(0 , (int)tree.size() - 1 , rng2)] , j});
                all.push_back(j);
            }
        }
    }
    for(int i =0 ; i < 25 ; i++)
    {
        if((1<<i) & X)
            continue;
        for(auto j : bits[i])
        {
            vp.push_back({all[myrand(0 , (int)all.size() - 1 , rng2)] , j});
        }
    }
    shuffle(vp.begin() , vp.end() , rng2);
    assert((int)vp.size() == N - 1);
    return vp;
}

Bob

#include <bits/stdc++.h>
#include "Bob.h"
using namespace std;
// you may define some global variables, but it does not work if you try to transfer any information from function Alice() to function Bob() through these variables.
// you had better not use the same global variables in function Alice() and in function Bob().
const int N = 5000;
const int B = 1000;
const int CNT = (N - B)/25;
int label[N + 1];

#define myrand( l , r , rng) uniform_int_distribution<int>(l , r)(rng)
long long Bob(std::vector<std::pair<int,int>> V){
    mt19937 rng1(1313);
    // add your code here
    vector<int> perm;
    set<int> s;
    for(int i = 1 ; i <= N ; i++)
    {
        perm.push_back(i);
    }
    shuffle(perm.begin() , perm.end() , rng1);
    for(int i = 0 ; i < B ; i++)
        s.insert(perm[i]);
    for(int i = 0 ; i < 25 ; i++)
    {
        for(int j = B + i * CNT ; j < B + (i + 1) * CNT ; j++)
        {
            label[perm[j]] = i;
        }
    }
    long long X = 0;
    for(auto [a , b] : V)
    {
        if(s.count(a) && !s.count(b))
        {
            X|=(1ll<<label[b]);
        }
    }
    return X;
}

• Subtask 1: 0 / 5
• Subtask 2: 0 / 30
• Subtask 3: 0 / 65