Submission #818913

#	Time	Username	Problem	Language	Result	Execution time	Memory
818913		LIF	Data Transfer (IOI19_transfer)	C++14	100 / 100	83 ms	2496 KiB

transfer

#include "transfer.h"
#include<bits/stdc++.h>
using namespace std;
int n;
vector<int> get_attachment(vector<int> source)
{
	int ans = 0;
	n = source.size();
	int need = 0;
	int mul = 1;
	if(n == 63) need = 6;
	else need = 8;
	//cout<<n<<endl;
	//cout<<need<<endl;
	for(int i=0;i<source.size();i++)if(source[i] == 1)ans ^= (i+1);
	vector<int> temp;
	for(int i=0;i<need;i++)temp.push_back(0);
	int nowbit = 0;
	//cout<<ans<<endl;
	while(ans > 0)
	{
		if(ans %2 == 0)temp[nowbit] = 0;
		else temp[nowbit] = 1;
		nowbit++;
		ans /= 2;
	}
	int kk = 0;
	vector<int> add;
	/*for(int i=temp.size()-1;i>=0;i--)cout<<temp[i]<<" ";
	cout<<endl;*/
	for(int i=temp.size()-1;i>=0;i--)add.push_back(temp[i]);
	for(int i=0;i<add.size();i++)kk ^= add[i];
	add.push_back(kk);
	/*for(int i=0;i<add.size();i++)cout<<add[i]<<" ";
	cout<<endl;*/
	/*for(int i=0;i<source.size();i++)cout<<source[i]<<" ";
	cout<<endl;*/
	return add;
}
vector<int> retrieve(vector<int> data)
{
	/*cout<<data.size()<<endl;
	cout<<"data: ";*/
/*	for(int i=n;i<data.size();i++)cout<<data[i];
	cout<<endl;*/
	int temp = 0;
	int n;
	if(data.size() == 70) n = 63;
	else n = 255;
	for(int i=n;i<data.size()-1;i++)temp ^= data[i];
	if(temp == data[data.size()-1]) // the part of ans1 has been changed.
	{
		int suxor = 0;
		int nowbit = 1;
		for(int i=data.size()-2;i>=n;i--)
		{
			if(data[i] == 1)suxor += nowbit;
			nowbit *= 2;
		}
	//	cout<<suxor<<endl;
		int temp2 = 0;
		for(int i=0;i<n;i++)if(data[i] == 1)temp2 ^= (i+1);
		if(suxor == temp2)
		{
			vector<int> ans;
			ans.clear();
			for(int i=0;i<n;i++)ans.push_back(data[i]);
			return ans;
		}
		else
		{
			int change = (suxor^temp2);
			data[change-1] ^=1;
			vector<int> ans;
			ans.clear();
			for(int i=0;i<n;i++)ans.push_back(data[i]);
			return ans;
		}
	}
	else
	{
		vector<int> ans;
		ans.clear();
		for(int i=0;i<n;i++)ans.push_back(data[i]);
		return ans;
	}
}

Compilation message (stderr)

transfer.cpp: In function 'std::vector<int> get_attachment(std::vector<int>)':
transfer.cpp:15:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   15 |  for(int i=0;i<source.size();i++)if(source[i] == 1)ans ^= (i+1);
      |              ~^~~~~~~~~~~~~~
transfer.cpp:32:15: 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=0;i<add.size();i++)kk ^= add[i];
      |              ~^~~~~~~~~~~
transfer.cpp:10:6: warning: unused variable 'mul' [-Wunused-variable]
   10 |  int mul = 1;
      |      ^~~
transfer.cpp: In function 'std::vector<int> retrieve(std::vector<int>)':
transfer.cpp:50:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   50 |  for(int i=n;i<data.size()-1;i++)temp ^= data[i];
      |              ~^~~~~~~~~~~~~~

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