Submission #829689

#	Time	Username	Problem	Language	Result	Execution time	Memory
829689		haxorman	Data Transfer (IOI19_transfer)	C++14	0 / 100	8 ms	2492 KiB

transfer

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

vector<int> get_attachment(vector<int> source) {
    vector<int> res;
    for (int j = 0; (1 << j) < source.size(); ++j) {
        int val = 0;
        for (int i = 0; i < source.size(); ++i) {
            if (i & (1 << j)) {
                val ^= source[i];
            }
        }
        res.push_back(val);
    }
    int end = 0;
    for (int i = 0; i < source.size(); ++i) {
        end ^= source[i];
    }
    res.push_back(end);

    return res;
}

vector<int> retrieve(vector<int> data) {
    bool smol = (data.size() == 70);

    int end = 0;
    vector<int> source;
    for (int i = 0; i < data.size() - (smol ? 7 : 9); ++i) {
        source.push_back(data[i]);
        end ^= data[i];
    }
    if (end == data.back()) {
        return source;
    }
    
    vector<int> lst;
    for (int i = data.size() - (smol ? 7 : 9); i < data.size() - 1; ++i) {
        lst.push_back(data[i]);
    }

    int bad = 0;
    for (int j = 0; (1 << j) < source.size(); ++j) {
        int val = 0;
        for (int i = 0; i < source.size(); ++i) {
            if (i & (1 << j)) {
                val ^= source[i];
            }
        }

        if (val != lst[j]) {
            bad += (1 << j);
        }
    }

    source[bad] ^= 1;
    return source;
}

Compilation message (stderr)

transfer.cpp: In function 'std::vector<int> get_attachment(std::vector<int>)':
transfer.cpp:7:30: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    7 |     for (int j = 0; (1 << j) < source.size(); ++j) {
      |                     ~~~~~~~~~^~~~~~~~~~~~~~~
transfer.cpp:9:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    9 |         for (int i = 0; i < source.size(); ++i) {
      |                         ~~^~~~~~~~~~~~~~~
transfer.cpp:17:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   17 |     for (int i = 0; i < source.size(); ++i) {
      |                     ~~^~~~~~~~~~~~~~~
transfer.cpp: In function 'std::vector<int> retrieve(std::vector<int>)':
transfer.cpp:30:23: 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() - (smol ? 7 : 9); ++i) {
      |                     ~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
transfer.cpp:39:50: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   39 |     for (int i = data.size() - (smol ? 7 : 9); i < data.size() - 1; ++i) {
      |                                                ~~^~~~~~~~~~~~~~~~~
transfer.cpp:44:30: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   44 |     for (int j = 0; (1 << j) < source.size(); ++j) {
      |                     ~~~~~~~~~^~~~~~~~~~~~~~~
transfer.cpp:46:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   46 |         for (int i = 0; i < source.size(); ++i) {
      |                         ~~^~~~~~~~~~~~~~~

• Subtask 1: 0 / 60
• Subtask 2: 0 / 40