#include <bits/stdc++.h>
using namespace std;
#ifdef tabr
#include "library/debug.cpp"
#else
#define debug(...)
#endif
#ifndef tabr
#include "transfer.h"
#endif
vector<int> get_attachment(vector<int> a) {
int n = (int) a.size();
int q = __builtin_popcount(n);
int c = 0;
for (int i = 0; i < n; i++) {
for (int j = 0; j < q; j++) {
if ((i + 1) & (1 << j)) {
c ^= a[i] << j;
}
}
}
for (int i = 0; i < (1 << (q + 1)); i++) {
if (__builtin_parity(i) == 0) {
if (c == 0) {
for (int j = 0; j < q + 1; j++) {
if (i & (1 << j)) {
a.emplace_back(1);
} else {
a.emplace_back(0);
}
}
return a;
}
c--;
}
}
assert(false);
return vector<int>();
}
vector<int> retrieve(vector<int> a) {
int n = 1;
int q = 2;
while (n + q != (int) a.size()) {
n *= 2;
n++;
q++;
}
return a;
int c = 0;
for (int i = n; i < n + q; i++) {
c ^= a[i] << (i - n);
}
if (__builtin_parity(c) == 1) {
a.resize(n);
return a;
}
int b = 0;
for (int i = 0; i < c; i++) {
if (__builtin_parity(i) == 0) {
b++;
}
}
for (int i = 0; i < n; i++) {
for (int j = 0; j < q; j++) {
if ((i + 1) & (1 << j)) {
b ^= a[i] << j;
}
}
}
if (b > 0) {
a[b - 1] ^= 1;
}
a.resize(n);
return a;
}
mt19937 rng((unsigned int) chrono::steady_clock::now().time_since_epoch().count());
int rand_int(int a, int b) { // [a, b]
return uniform_int_distribution<int>(a, b)(rng);
}
#ifdef tabr
int main() {
ios::sync_with_stdio(false);
cin.tie(0);
int n = 7;
int tt = 100000;
while (tt--) {
vector<int> a(n);
for (int i = 0; i < n; i++) {
a[i] = rand_int(0, 1);
}
auto b = get_attachment(a);
int pos = rand_int(-1, (int) b.size() - 1);
if (pos >= 0) {
b[pos] ^= 1;
}
auto c = retrieve(b);
if (a == c) {
// cerr << "OK" << endl;
} else {
cerr << "NG" << endl;
debug(pos);
debug(a);
debug(b);
debug(c);
}
}
return 0;
}
#endif
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
4 ms |
876 KB |
WA in grader: wrong source retrieval |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
10 ms |
4452 KB |
WA in grader: wrong source retrieval |
2 |
Halted |
0 ms |
0 KB |
- |