Submission #1006182

#	Time	Username	Problem	Language	Result	Execution time	Memory
1006182		HishamAlshehri	Data Transfer (IOI19_transfer)	C++17	Compilation error	0 ms	0 KiB

transfer

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

vector<int> get_attachment(vector<int> source) {
	int x = 0, cnt = 0;
	for (int i = 0; i < source.size(); i++)
	{
		if (source[i])
		{
			x ^= (i + 1);
			cnt++;
		}
	}
	vector<int>ans = source;
	while (x)
	{
		ans.push_back(x % 2);
		x /= 2;
	}
	ans.push_back(cnt % 2);
	return ans;
}

vector<int> retrieve(vector<int> data) {
	int x1 = 0, k = data[data.size() - 1], cnt = 0;
	int n = (data.size() > 255 ? 255 : 63);
	for (int i = 0; i < n; i++)
	{
		if (data[i])
		{
			cnt++;
			x1 ^= (i + 1);
		}
	}
	int x2 = 0;
	for (int i = n; i < data.size() - 1; i++)
	{
		x2 += data[i] * (1 << (i - n + 1));		
	}
	if (x1 != x2 && cnt % 2 != k)
		data[x2 ^ x1] ^= 1;
	return vector<int>(data.begin(), data.begin() + n);
}

int main()
{
    int t;
    cin >> t;
    while (t--)
    {
        vector<int> b;
        int c;
        cin >> c;
		string s;
		cin >> s;
		for (int j = 0; j < s.size(); j++) {
			b.push_back(int(s[j] - '0'));
		}
        
        vector<int>ans = retrieve(get_attachment(b));
		for (int i = 0; i < ans.size(); i++)
		{
			if (ans[i] != b[i])
			{
				cout << "NO\n";
				return 0;
			}
		}
		cout << "YES\n";
    }
}

Compilation message (stderr)

transfer.cpp: In function 'std::vector<int> get_attachment(std::vector<int>)':
transfer.cpp:6:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    6 |  for (int i = 0; i < source.size(); i++)
      |                  ~~^~~~~~~~~~~~~~~
transfer.cpp: In function 'std::vector<int> retrieve(std::vector<int>)':
transfer.cpp:36:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   36 |  for (int i = n; i < data.size() - 1; i++)
      |                  ~~^~~~~~~~~~~~~~~~~
transfer.cpp: In function 'int main()':
transfer.cpp:56:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   56 |   for (int j = 0; j < s.size(); j++) {
      |                   ~~^~~~~~~~~~
transfer.cpp:61:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   61 |   for (int i = 0; i < ans.size(); i++)
      |                   ~~^~~~~~~~~~~~
/usr/bin/ld: /tmp/cclsN4vx.o: in function `main':
grader.cpp:(.text.startup+0x0): multiple definition of `main'; /tmp/ccXcpeMu.o:transfer.cpp:(.text.startup+0x0): first defined here
collect2: error: ld returned 1 exit status