Submission #980599

#	Time	Username	Problem	Language	Result	Execution time	Memory
980599		oleh1421	Longest Trip (IOI23_longesttrip)	C++17	5 / 100	7 ms	500 KiB

longesttrip

#include "longesttrip.h"
#include <bits/stdc++.h>
using namespace std;
std::vector<int> longest_trip(int N, int D)
{
    vector<int>A={0},B;
    for (int i=1;i<N;i++){
        if (are_connected({A.back()},{i})){
            A.push_back(i);
        } else {
            if (B.empty() || are_connected({B.back()},{i})){
                B.push_back(i);
            } else {
                reverse(B.begin(),B.end());
                for (auto i:B) A.push_back(i);
                B={i};
            }
        }
    }
    if (B.empty()) return A;
    if (are_connected({A[0],A.back()},{B[0],B.back()})){
        if (are_connected({A[0]},{B[0],B.back()})){
            if (are_connected({A[0]},{B[0]})){
                reverse(B.begin(),B.end());
                for (auto i:A){
                    B.push_back(i);
                }
                return B;
            } else {
                for (auto i:A){
                    B.push_back(i);
                }
                return B;
            }
        } else {
            if (are_connected({A.back()},{B[0]})){
                for (auto i:B){
                    A.push_back(i);
                }
                return A;
            } else {
                reverse(B.begin(),B.end());
                for (auto i:B){
                    A.push_back(i);
                }
                return A;
            }
        }
    }
    if (!are_connected(A,B)){
        if (A.size()>B.size()) return A;
        else return B;
    }
    vector<int>rem,A0,B0;
    {
        int pos=0;
        for (int i=8;i>=0;i--){
            pos+=(1<<i);
            if (pos>=A.size()){
                pos-=(1<<i);
                continue;
            }
            vector<int>C;
            for (int j=0;j<pos;j++) C.push_back(A[j]);
            if (are_connected(C,B)){
                pos-=(1<<i);
            }
        }
        rem=A;
        A={A[pos]};
        swap(A,B);
    }
    A0=rem;
    {
        int pos=0;
        for (int i=8;i>=0;i--){
            pos+=(1<<i);
            if (pos>=A.size()){
                pos-=(1<<i);
                continue;
            }
            vector<int>C;
            for (int j=0;j<pos;j++) C.push_back(A[j]);
            if (are_connected(C,B)){
                pos-=(1<<i);
            }
        }
        rem=A;
        A={A[pos]};
        swap(A,B);
    }
    B0=rem;
    vector<int>ans;
    for (auto i:A0){
        if (i==A[0]) continue;
        ans.push_back(i);
    }
    ans.push_back(A[0]);
    ans.push_back(B[0]);
    for (auto i:B0){
        if (i==B[0]) continue;
        ans.push_back(i);
    }
    return ans;
}

Compilation message (stderr)

longesttrip.cpp: In function 'std::vector<int> longest_trip(int, int)':
longesttrip.cpp:59:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   59 |             if (pos>=A.size()){
      |                 ~~~^~~~~~~~~~
longesttrip.cpp:78:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   78 |             if (pos>=A.size()){
      |                 ~~~^~~~~~~~~~

• Subtask 0: 0 / 0
• Subtask 1: 5 / 5
• Subtask 2: 0 / 10
• Subtask 3: 0 / 25
• Subtask 4: 0 / 60