# | Time | Username | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
1201679 | adiyer | Permutation (APIO22_perm) | C++20 | 0 ms | 0 KiB |
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
vector < int > construct_permutation(ll k){
k--;
int x = 0, y = 0;
vector < int > ans[60];
for(ll bit = 59; bit >= 1; bit--){
while(k >= (1ll << bit) - 1){
k -= (1ll << bit) - 1, x++;
for(int i = 0; i < bit; i++) ans[x].push_back(y++);
}
}
for(int i = x; i >= 1; i--){
for(int val : ans[i]){
ans[0].push_back(val);
}
}
return ans[0];
}
static long long MX = 1e18;
static bool check_permutation(vector<int> v)
{
sort(v.begin(),v.end());
for(int i=0;i<v.size();i++)
if(v[i]!=i) return 0;
return 1;
}
long long count_increasing(const vector<int>& v) {
vector<long long> dp(v.size() + 1, 0);
dp[0] = 1;
for (int x : v)
{
for (int i = 0; i <= x; i++)
{
dp[x+1] += dp[i];
dp[x+1] = min(dp[x+1],MX+1);
}
}
long long result = 0;
for (int i = 0; i <= (int)v.size(); i++){
result += dp[i];
result = min(result,MX+1);
}
return result;
}
int main() {
int t;
assert(1 == scanf("%d", &t));
while(t--)
{
long long k;
assert(1 == scanf("%lld",&k));
vector<int> ret=construct_permutation(k);
if(!check_permutation(ret))
{
printf("WA: Returned array is not a permutation\n");
exit(0);
}
long long inc=count_increasing(ret);
if(inc!=k)
{
if(inc==MX+1)
printf("WA: Expected %lld increasing subsequences, found more than %lld\n",k, MX);
else
printf("WA: Expected %lld increasing subsequences, found %lld\n",k,inc);
exit(0);
}
printf("%d\n",(int)ret.size());
for(int i=0;i<ret.size();i++)
{
printf("%d",ret[i]);
if(i+1==ret.size())
printf("\n");
else
printf(" ");
}
}
return 0;
}