#if defined(ONPC) && !defined(_GLIBCXX_ASSERTIONS)
#define _GLIBCXX_ASSERTIONS
#endif
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/detail/standard_policies.hpp>
#ifdef ONPC
#include "t_debug.cpp"
#else
#define debug(...) 42
#endif
#define allit(a) (a).begin(), (a).end()
#define sz(a) ((int) (a).size())
using namespace std;
using ll = long long;
using vi = vector<int>;
namespace pd = __gnu_pbds;
template<typename K>
using ordered_set = pd::tree<K, pd::null_type, less<int>, pd::rb_tree_tag, pd::tree_order_statistics_node_update>;
template<typename... T>
using gp_hash_table = pd::gp_hash_table<T...>;//simple using statement gives warnings
const int INF = 1e9;
const ll INFL = 1e18;
const int N = 1e5;
const int K = 10; // 20
const int RANDOM = chrono::high_resolution_clock::now().time_since_epoch().count();
mt19937 rng(RANDOM);
int solve() {
int n, s; cin >> n >> s;
vi a(n); for (auto& i : a) cin >> i;
vector<pair<int,int>> res;
#define DO(i, j) {res.emplace_back(i, j); a[i] ^= a[j];}
auto print = [&]() {
for (int i = 0; i < n; i++) cerr << bitset<K>(a[i]) << ' ';
cerr << endl;
};
for (int b = K-1; b >= 0; b--) {
//carry bit to the end
int end = n-1;
for (int i = 0; i < end; i++) {
if (a[i] & (1<<b)) {
if (! (a[i+1] & (1 << b)))
DO(i+1, i);
}
}
debug(a, end);
}
#ifdef ONPC
debug(a);
for (int i = 0; i < n-1; i++) {
assert(s == 1 ? a[i] < a[i+1] : a[i] <= a[i+1]);
}
#endif
//#ifndef ONPC
cout << res.size() << '\n';
for (auto [i, j] : res) cout << i+1 << ' ' << j+1 << '\n';
//#endif
return 0;
}
signed main() {
cin.tie(0)->sync_with_stdio(0);
int t = 1;
#ifdef ONPC
cin >> t;
#endif
while (t-- && cin) {
if (solve()) break;
#ifdef ONPC
cout << "____________________" << endl;
#endif
}
return 0;
}
Compilation message
xorsort.cpp: In function 'int solve()':
xorsort.cpp:10:24: warning: statement has no effect [-Wunused-value]
10 | #define debug(...) 42
| ^~
xorsort.cpp:50:9: note: in expansion of macro 'debug'
50 | debug(a, end);
| ^~~~~
xorsort.cpp:36:10: warning: variable 'print' set but not used [-Wunused-but-set-variable]
36 | auto print = [&]() {
| ^~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
0 ms |
212 KB |
Not sorted |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
0 ms |
212 KB |
Not sorted |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
1 ms |
212 KB |
Not sorted |
2 |
Halted |
0 ms |
0 KB |
- |