oj.uz

Submission #443430

# Submission time Handle Problem Language Result Execution time Memory
443430 2021-07-10T13:18:40 Z chicken337 Data Transfer (IOI19_transfer) C++14
100 / 100
 69 ms 2540 KB 
#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;
    }
}**/

Compilation message

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
60.0 / 60.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 620 KB Output is correct
2 Correct 3 ms 620 KB Output is correct
3 Correct 3 ms 624 KB Output is correct
4 Correct 3 ms 628 KB Output is correct
5 Correct 3 ms 612 KB Output is correct
6 Correct 3 ms 628 KB Output is correct
7 Correct 3 ms 616 KB Output is correct
8 Correct 3 ms 620 KB Output is correct
9 Correct 3 ms 620 KB Output is correct
10 Correct 3 ms 708 KB Output is correct
11 Correct 3 ms 620 KB Output is correct
12 Correct 3 ms 704 KB Output is correct
13 Correct 3 ms 620 KB Output is correct
14 Correct 4 ms 628 KB Output is correct
15 Correct 3 ms 692 KB Output is correct
16 Correct 3 ms 620 KB Output is correct
17 Correct 3 ms 628 KB Output is correct

Subtask #2
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 44 ms 2428 KB Output is correct
2 Correct 44 ms 2428 KB Output is correct
3 Correct 46 ms 2540 KB Output is correct
4 Correct 55 ms 2464 KB Output is correct
5 Correct 47 ms 2476 KB Output is correct
6 Correct 45 ms 2468 KB Output is correct
7 Correct 44 ms 2464 KB Output is correct
8 Correct 47 ms 2464 KB Output is correct
9 Correct 46 ms 2464 KB Output is correct
10 Correct 45 ms 2464 KB Output is correct
11 Correct 46 ms 2432 KB Output is correct
12 Correct 46 ms 2464 KB Output is correct
13 Correct 44 ms 2464 KB Output is correct
14 Correct 45 ms 2460 KB Output is correct
15 Correct 45 ms 2476 KB Output is correct
16 Correct 45 ms 2476 KB Output is correct
17 Correct 52 ms 2480 KB Output is correct
18 Correct 45 ms 2464 KB Output is correct
19 Correct 69 ms 2464 KB Output is correct