Submission #352206

#	Time	Username	Problem	Language	Result	Execution time	Memory
352206		talant117408	Parrots (IOI11_parrots)	C++17	99 / 100	18 ms	1572 KiB

encoder

#include "encoder.h"
#include "encoderlib.h"
#ifndef EVAL
#include "grader.cpp"
#endif
#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef pair <int, int> pii;
typedef pair <ll, ll> pll;

#define precision(n) fixed << setprecision(n)
#define pb push_back
#define ub upper_bound
#define lb lower_bound
#define mp make_pair
#define eps (double)1e-9
#define PI 2*acos(0.0)
#define endl "\n"
#define sz(v) int((v).size())
#define all(v) v.begin(),v.end()
#define rall(v) v.rbegin(),v.rend()
#define do_not_disturb ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define OK cout << "OK" << endl;

void encode(int N, int M[]){
    int res = 0, ind = -1;
    vector <int> ans, vec;
    for(int i = 0; i < N; i++){
        ans.pb(M[i]);
        vec.pb(M[i]);
        for(int bit = 0; bit < 4; bit++)
            if(M[i]&(1<<bit))
                res++;
        for(int bit = 0; bit < 4; bit++)
            if(M[i]&(1<<(bit+4)))
                res += 2;
    }
    for(int k = 0; k < 256; k++){
        for(auto &to : vec) to ^= k;
        int cnt = 0;
        for(int i = 0; i < N; i++){
            for(int bit = 0; bit < 4; bit++)
                if(vec[i]&(1<<bit))
                    cnt++;
            for(int bit = 0; bit < 4; bit++)
                if(vec[i]&(1<<(bit+4)))
                    cnt += 2;
        }
        if(cnt < res){
            ind = k;
            res = cnt;
            ans = vec;
        }
        for(auto &to : vec) to ^= k;
    }
    vector <int> one;
    for(int i = 0; i < N; i++){
        int num = i;
        for(int bit = 0; bit < 4; bit++){
            if(ans[i]&(1<<bit)){
                if(!bit) one.pb(num);
                else if(bit == 1) one.pb(num+64);
                else if(bit == 2) one.pb(num+128);
                else one.pb(num+192);
            }
        }
        for(int bit = 0; bit < 4; bit++){
            if(ans[i]&(1<<(bit+4))){
                if(!bit){
                    one.pb(num);
                    one.pb(num);
                }
                else if(bit == 1){
                    one.pb(num+64);
                    one.pb(num+64);
                }
                else if(bit == 2){
                    one.pb(num+128);
                    one.pb(num+128);
                }
                else{
                    one.pb(num+192);
                    one.pb(num+192);
                }
            }
        }
    }
    for(auto to : one) send(to);
    if(ind == -1){
        for(int i = 0; i < 5; i++)
            send(0);
    }
    else{
        for(int i = 0; i < 4; i++){
            send(ind);
        }
    }
}

decoder

#include "decoder.h"
#include "decoderlib.h"
#ifndef EVAL
#include "grader.cpp"
#endif
#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef pair <int, int> pii;
typedef pair <ll, ll> pll;

#define precision(n) fixed << setprecision(n)
#define pb push_back
#define ub upper_bound
#define lb lower_bound
#define mp make_pair
#define eps (double)1e-9
#define PI 2*acos(0.0)
#define endl "\n"
#define sz(v) int((v).size())
#define all(v) v.begin(),v.end()
#define rall(v) v.rbegin(),v.rend()
#define do_not_disturb ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define OK cout << "OK" << endl;

void decode(int N, int L, int X[]){
    vector <int> cnt(256), ans(N);
    int flag = 1, xr;
    for(int i = 0; i < L; i++){
        cnt[X[i]]++;
    }
    if(cnt[0] > 4){
        flag = 0;
        cnt[0] -= 5;
    }
    else{
        for(int i = 0; i < 256; i++){
            if(cnt[i] > 3){
                cnt[i] -= 4;
                xr = i;
                break;
            }
        }
    }
    for(int i = 0; i < 256; i++){
        if(cnt[i] > 1){
            cnt[i] -= 2;
            int ind = 0, which = 0;
            for(int bit = 0; bit < 6; bit++){
                if(i&(1<<bit)) ind |= (1<<bit);
            }
            if((i&(1<<6)) && (i&(1<<7))) which = 7;
            else if(i&(1<<7)) which = 6;
            else if(i&(1<<6)) which = 5;
            else which = 4;
            ans[ind] |= (1<<which);
        }
        if(cnt[i]){
            cnt[i]--;
            int ind = 0, which = 0;
            for(int bit = 0; bit < 6; bit++){
                if(i&(1<<bit)) ind |= (1<<bit);
            }
            if((i&(1<<6)) && (i&(1<<7))) which = 3;
            else if(i&(1<<7)) which = 2;
            else if(i&(1<<6)) which = 1;
            else which = 0;
            ans[ind] |= (1<<which);
        }
    }
    for(auto &to : ans){
        if(flag) to ^= xr;
    }
    for(auto to : ans) output(to);
}
/*
8
0 0 1 1 0 0 1 0

6 
1 255 13 26 49 216
*/

Compilation message (stderr)

decoder.cpp: In function 'void decode(int, int, int*)':
decoder.cpp:74:21: warning: 'xr' may be used uninitialized in this function [-Wmaybe-uninitialized]
   74 |         if(flag) to ^= xr;
      |                  ~~~^~~~~

• Subtask 1: 17 / 17
• Subtask 2: 17 / 17
• Subtask 3: 18 / 18
• Subtask 4: 29 / 29
• Subtask 5: 18 / 19