Submission #916500

#	Time	Username	Problem	Language	Result	Execution time	Memory
916500		wii	Permutation (APIO22_perm)	C++17	Compilation error	0 ms	0 KiB

perm

#include <bits/stdc++.h>
#include <perm.h>

using namespace std;

void dnc(deque<int> &v, int id, int u) {
    if (id < 0) return;

    if (u & 1) {
        dnc(v, id - 1, u >> 1);
        v.push_back(id);
    } else {
        dnc(v, id - 1, u - 1);
        v.push_front(id);
    }
}

vector<int> construct_permutation(int k) {
    k -= 1;

    int cnt = 0;
    for (int x = k; x > 0; x = (~x & 1 ? --x : x >> 1), ++cnt);

    deque<int> ans;
    dnc(ans, cnt - 1, k);

    return vector<int>(ans.begin(), ans.end());
}

Compilation message (stderr)

perm.cpp: In function 'std::vector<int> construct_permutation(int)':
perm.cpp:22:30: warning: operation on 'x' may be undefined [-Wsequence-point]
   22 |     for (int x = k; x > 0; x = (~x & 1 ? --x : x >> 1), ++cnt);
      |                            ~~^~~~~~~~~~~~~~~~~~~~~~~~~
perm.cpp:22:30: warning: operation on 'x' may be undefined [-Wsequence-point]
/usr/bin/ld: /tmp/ccrnrjGm.o: in function `main':
grader.cpp:(.text.startup+0x240): undefined reference to `construct_permutation(long long)'
collect2: error: ld returned 1 exit status