제출 #443430

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
443430		chicken337	Data Transfer (IOI19_transfer)	C++14	100 / 100	69 ms	2540 KiB

transfer

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

vector<int> get_attachment(vector<int> source){
    vector<int> ans; int xr = 0;
    for(int i = 0; i < source.size(); i ++)
        xr ^= source[i] * (i+1);
    int last = 0, rounds = source.size() < 64 ? 6 : 8;
    for(int i = 0; i < rounds; i ++){
        ans.push_back(xr & 1);
        if(xr & 1) last ^= 1;
        xr >>= 1;
    }
    ans.push_back(last);
    return ans;
}
vector<int> retrieve(vector<int> data){
    int last = data.back(); data.pop_back();
    int actual = 0, xr = 0;
    int rounds = data.size() < 71 ? 6 : 8;
    for(int i = 0; i < rounds; i ++){
        xr <<= 1; xr += data.back();
        if(data.back()) last ^= 1;
        data.pop_back();
    }
    if(actual != last)
        return vector<int>(data.begin(), data.end());
    int x = 0;
    for(int i = 0; i < data.size(); i ++)
        x ^= data[i] * (i+1);
    int err = xr ^ x;
    if(err) data[err-1] ^= 1;
    return data;
}
/**
int main(){
    for(int i = 0; i < 100; i ++){
        bool correct = true;
        vector<int> gen_seq;
        int len = rand() % 255 + 1;
        for(int i = 0; i < len; i ++)
            gen_seq.push_back(rand()&1);
        cout << "Generation OK" << endl;
        vector<int> attach = get_attachment(gen_seq);
        if(len < 64 && attach.size()>7) correct = 0;
        if(len > 63 && attach.size()>9) correct = 0;
        cout << "Attachment OK" << endl;
        vector<int> nans;
        for(int it : gen_seq) nans.push_back(it);
        for(int it : attach) nans.push_back(it);
        vector<int> res = retrieve(nans);
        cout << "Retrieval OK" << endl;
        if(res.size() != len) correct = 0, cout << "WRONG LENGTH" << endl;
        else for(int i = 0; i < res.size(); i ++)
            if(res[i] != gen_seq[i]) correct = 0, cout << "WRONG ELEMENT" << endl;
        cout << (correct ? "CORRECT" : "INCORRECT") << " with length " << len << endl;
    }
}**/

컴파일 시 표준 에러 (stderr) 메시지

transfer.cpp: In function 'std::vector<int> get_attachment(std::vector<int>)':
transfer.cpp:7:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    7 |     for(int i = 0; i < source.size(); i ++)
      |                    ~~^~~~~~~~~~~~~~~
transfer.cpp: In function 'std::vector<int> retrieve(std::vector<int>)':
transfer.cpp:30:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   30 |     for(int i = 0; i < data.size(); i ++)
      |                    ~~^~~~~~~~~~~~~

• Subtask 1: 60 / 60
• Subtask 2: 40 / 40