Submission #679304

#	Time	Username	Problem	Language	Result	Execution time	Memory
679304		ar88lo	Data Transfer (IOI19_transfer)	C++14	100 / 100	132 ms	2548 KiB

transfer

#include "transfer.h"

std::vector<int> get_attachment(std::vector<int> source) {

    int x,lg,cnt;
    std::vector<int> ret;
    cnt = x = 0; lg = (source.size() == 63)?6:8;
    for(int i = 1; i <= source.size(); i++){
        if(source[i-1]){
            x ^= i;
        }
    }

    while(x > 0){
        cnt += x%2;
        ret.push_back(x%2);
        x/=2;
    }
    while(ret.size() < lg){
        ret.push_back(0);
    }
    ret.push_back(cnt%2);
    return ret;
}

std::vector<int> retrieve(std::vector<int> data) {

    int a,x,k,lg,cnt;
    std::vector<int> ret;
    k = 1; lg = (data.size() == 70)?6:8;
    cnt = x = a = 0;
    for(int i = data.size() - lg - 1; i < data.size() - 1; i++){
        if(data[i]) cnt++;
        a += data[i]*k;
        k*=2;
    }

    for(int i = 0; i < data.size() - lg - 1; i++){
        ret.push_back(data[i]);
    }

    if(data[data.size()-1] == cnt%2){

        for(int i = 1; i <= data.size() - lg - 1; i++){
            if(data[i-1]){
                x ^= i;
            }
        }
        x = x^a;
        if(x!=0) ret[x-1] = !ret[x-1];

    }
    return ret;

}

Compilation message (stderr)

transfer.cpp: In function 'std::vector<int> get_attachment(std::vector<int>)':
transfer.cpp:8:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    8 |     for(int i = 1; i <= source.size(); i++){
      |                    ~~^~~~~~~~~~~~~~~~
transfer.cpp:19:22: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   19 |     while(ret.size() < lg){
      |           ~~~~~~~~~~~^~~~
transfer.cpp: In function 'std::vector<int> retrieve(std::vector<int>)':
transfer.cpp:32:41: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   32 |     for(int i = data.size() - lg - 1; i < data.size() - 1; i++){
      |                                       ~~^~~~~~~~~~~~~~~~~
transfer.cpp:38:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   38 |     for(int i = 0; i < data.size() - lg - 1; i++){
      |                    ~~^~~~~~~~~~~~~~~~~~~~~~
transfer.cpp:44:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   44 |         for(int i = 1; i <= data.size() - lg - 1; i++){
      |                        ~~^~~~~~~~~~~~~~~~~~~~~~~

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