Submission #718576

#	Time	Username	Problem	Language	Result	Execution time	Memory
718576		lam	Permutation (APIO22_perm)	C++17	100 / 100	2 ms	340 KiB

perm

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

void add(vector <int> &ans, vector <int> tmp)
{
    vector <int> tmp2;
    for (int i:tmp) if (i>0) tmp2.push_back(i);
    sort(tmp2.begin(),tmp2.end());
    for (int i:tmp2)
        for (int &j:ans) if (j>=i) j++;
    int bound = ans.size() + tmp.size();
    for (int i:tmp) if (i<=0) ans.push_back(bound+i);
    else ans.push_back(i);
}
vector<int> construct_permutation(long long k)
{
    vector <int> res;
    if (k==1) return res;
    if (k==2) return vector <int>({0});
    if (k==3) return vector <int>({1,0});
    vector <int> digits;
    while (k>0)
    {
        digits.push_back(int(k&1));
        k>>=1;
    }
    reverse(digits.begin(),digits.end());
    int it=1;
    if (digits[1]==0)
    {
        if (digits[2]==0) res=vector<int>({3,2,1});
        else res=vector <int>({2,3,1});
        it+=2;
    }
    else
    {
        res=vector<int>({2,1});
        it++;
    }
    while (it+1<digits.size())
        if (digits[it]==0)
    {
        add(res,{0});
        it++;
    }
    else
    {
        if (digits[it+1]==0) add(res,{-1,1,0});
        else add(res,{-1,0,3});
        it+=2;
    }
    if (it<digits.size())
    {
        if (digits[it]==0) add(res,{0});
        else add(res,{0,1});
    }
    for (int &i:res) i--;
    return res;
}

Compilation message (stderr)

perm.cpp: In function 'std::vector<int> construct_permutation(long long int)':
perm.cpp:43:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   43 |     while (it+1<digits.size())
      |            ~~~~^~~~~~~~~~~~~~
perm.cpp:55:11: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   55 |     if (it<digits.size())
      |         ~~^~~~~~~~~~~~~~

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