#include "perm.h"
#include <bits/stdc++.h>
using namespace std;
#define ll long long
// #define int ll
#define FOR(i, a, b) for (int i = (a); i < (b); i++)
#define REP(i, n) FOR(i, 0, n)
#define REP1(i, n) FOR(i, 1, n+1)
#define RREP(i, n) for (int i = (n)-1; i >= 0; i--)
#define pii pair<int, int>
#define f first
#define s second
#define pb push_back
#define ALL(x) (x).begin(), (x).end()
#define SZ(x) (int)((x).size())
namespace{
const ll maxn = 1e5+5;
const ll mod = 1e9+7;
const ll inf = (1ll<<60);
}
pair<int, vector<int>> make_bin(long long k, int cur){ // other method: make with binary
k--;
vector<int> ret;
if (k == 0) return {cur, ret};
for (int i = 6; i >= 1; i--){
ll tmp = (1<<i)-1;
while (k >= tmp){
k -= tmp;
vector<int> poo;
REP(j, i) poo.pb(cur++);
RREP(j, SZ(poo)) ret.pb(poo[j]);
}
}
reverse(ALL(ret));
return {cur, ret};
}
pair<int, vector<int>> make_bao(long long k, int cur){
k--;
vector<int> ret;
if (k == 0) return {cur, ret};
REP(i, k) ret.pb(cur++);
reverse(ALL(ret));
return {cur, ret};
}
std::vector<int> construct_permutation(long long k){
k--; // imma make it a bunch of sums
vector<int> ret; // initially all reversed
int cur = 0;
for (int b = 55; b >= 0; b -= 5){
ll tmp = (1ll<<b);
int cnt = 0;
while(tmp * (cnt+1) - 1 <= k){
cnt++;
}
if (cnt == 0) continue;
cnt--;
k -= tmp * (cnt+1) - 1;
// goal is to have other side of product = cnt+1
vector<int> ra, rb;
REP(i, b){
ra.pb(cur++);
}
pair<int, vector<int>> c1 = make_bin(cnt+1, cur), c2 = make_bao(cnt+1, cur);
if (c1.f < c2.f){
rb = c1.s;
cur = c1.f;
}
else{
rb = c2.s;
cur = c2.f;
}
RREP(i, SZ(rb)) ret.pb(rb[i]);
RREP(i, SZ(ra)) ret.pb(ra[i]);
}
reverse(ALL(ret));
return ret;
}
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