Submission #986307

#	Time	Username	Problem	Language	Result	Execution time	Memory
986307		siewjh	Permutation (APIO22_perm)	C++17	100 / 100	2 ms	600 KiB

perm

#include "perm.h"
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;

vector<int> construct_permutation(ll k){
	vector<ll> b4;
	while (k){
		b4.push_back(k & 3); k >>= 2;
	}
	int sz = b4.size();
	vector<int> vec;
	if (b4[sz - 1] == 2) vec = {0};
	else if (b4[sz - 1] == 3) vec = {1, 0};
	for (int i = sz - 2; i >= 0; i--){
		int amt = vec.size();
		if (b4[i] == 0){
			vec.push_back(amt); vec.push_back(amt + 1);
		}
		else if (b4[i] == 1){
			vec.push_back(amt); vec.push_back(amt + 1); vec.insert(vec.begin(), amt + 2);
		}
		else if (b4[i] == 2){
			vec.push_back(amt); vec.push_back(amt + 2); vec.insert(vec.begin(), amt + 1);
		}
		else{
			if (vec.size() >= 2 && vec[0] > vec[1]){
				vec.push_back(amt); vec.push_back(amt + 1); vec.insert(vec.begin() + 2, amt + 2);
			}
			else{
				vec.push_back(amt); vec.push_back(amt + 2); vec.insert(vec.begin(), amt + 1); vec.insert(vec.begin(), amt + 3);
			}
		}
	}
	return vec;
}

• Subtask 1: 10 / 10
• Subtask 2: 90 / 90