Submission #897045

#	Time	Username	Problem	Language	Result	Execution time	Memory
897045		irmuun	Longest Trip (IOI23_longesttrip)	C++17	15 / 100	8 ms	608 KiB

longesttrip

#include<bits/stdc++.h>
#include "longesttrip.h"
 
using namespace std;
 
#define ll long long
#define pb push_back
#define ff first
#define ss second
#define all(s) s.begin(),s.end()
#define rall(s) s.rbegin(),s.rend()
 
vector<int>longest_trip(int N, int D){
    vector<int>ans;
    if(D==3){
        vector<int>ans(N);
        iota(all(ans),0);
        return ans;
    }
    if(D==2){
        vector<int>ans;
        ans.pb(0);
        int l=0,r=0;
        int x;
        for(int i=1;i<N;i++){
            if(are_connected({0},{i})==true){
                ans.pb(i);
                x=i;
                r=i;
                break;
            }
        }
        for(int i=1;i<N;i++){
            if(i!=x){
                if(are_connected({l},{i})){
                    ans.insert(ans.begin(),i);
                    l=i;
                }
                else{
                    ans.pb(i);
                    r=i;
                }
            }
        }
        return ans;
    }
    vector<int>v,u;
    v.pb(0);
    u.pb(1);
    for(int i=2;i<N;i++){
        if(are_connected({v.back()},{i})==true){
            v.pb(i);
        }
        else if(are_connected({u.back()},{i})==true){
            u.pb(i);
        }
        else{
            reverse(all(u));
            v.insert(v.end(),all(u));
            u={i};
        }
    }
    if(are_connected(v,u)==false){
        if(v.size()>=u.size()){
            return v;
        }
        return u;
    }
    //now need combine 2 cycles
    vector<int>v1=v,u1=u;
    while(v1.size()>1){
        vector<int>l,r;
        for(int i=0;i<v1.size()/2;i++){
            l.pb(v1[i]);
        }
        for(int i=v1.size()/2;i<v1.size();i++){
            r.pb(v1[i]);
        }
        if(are_connected(l,u1)==true){
            v1=l;
        }
        else{
            v1=r;
        }
    }
    while(u1.size()>1){
        vector<int>l,r;
        for(int i=0;i<u1.size()/2;i++){
            l.pb(v1[i]);
        }
        for(int i=u1.size()/2;i<u1.size();i++){
            r.pb(v1[i]);
        }
        if(are_connected(v1,l)==true){
            v1=l;
        }
        else{
            v1=r;
        }
    }
    for(int i=0;i<v.size();i++){
        if(v[i]==v1[0]){
            rotate(v.begin(),v.begin()+i,v.end());
            break;
        }
    }
    for(int i=0;i<u.size();i++){
        if(u[i]==u1[0]){
            rotate(u.begin(),u.begin()+i,u.end());
            break;
        }
    }
    reverse(all(u));
    v.insert(v.end(),all(u));
    return v;
}

Compilation message (stderr)

longesttrip.cpp: In function 'std::vector<int> longest_trip(int, int)':
longesttrip.cpp:23:17: warning: variable 'r' set but not used [-Wunused-but-set-variable]
   23 |         int l=0,r=0;
      |                 ^
longesttrip.cpp:73:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   73 |         for(int i=0;i<v1.size()/2;i++){
      |                     ~^~~~~~~~~~~~
longesttrip.cpp:76:32: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   76 |         for(int i=v1.size()/2;i<v1.size();i++){
      |                               ~^~~~~~~~~~
longesttrip.cpp:88:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   88 |         for(int i=0;i<u1.size()/2;i++){
      |                     ~^~~~~~~~~~~~
longesttrip.cpp:91:32: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   91 |         for(int i=u1.size()/2;i<u1.size();i++){
      |                               ~^~~~~~~~~~
longesttrip.cpp:101:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  101 |     for(int i=0;i<v.size();i++){
      |                 ~^~~~~~~~~
longesttrip.cpp:107:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  107 |     for(int i=0;i<u.size();i++){
      |                 ~^~~~~~~~~
longesttrip.cpp:34:13: warning: 'x' may be used uninitialized in this function [-Wmaybe-uninitialized]
   34 |             if(i!=x){
      |             ^~

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