Submission #1161116

#	Time	Username	Problem	Language	Result	Execution time	Memory
1161116		steveonalex	Longest Trip (IOI23_longesttrip)	C++20	15 / 100	5 ms	420 KiB

longesttrip

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef unsigned long long ull;

#define MASK(i) (1ULL << (i))
#define GETBIT(mask, i) (((mask) >> (i)) & 1)
#define ALL(v) (v).begin(), (v).end()

ll max(ll a, ll b){return (a > b) ? a : b;}
ll min(ll a, ll b){return (a < b) ? a : b;}
ll gcd(ll a, ll b){return __gcd(a, b);}
ll lcm(ll a, ll b){return a / gcd(a, b) * b;}

ll LASTBIT(ll mask){return (mask) & (-mask);}
int pop_cnt(ull mask){return __builtin_popcountll(mask);}
int ctz(ull mask){return __builtin_ctzll(mask);}
int logOf(ull mask){return 63 - __builtin_clzll(mask);}

//mt19937_64 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
mt19937_64 rng(1);
ll rngesus(ll l, ll r){return l + (ull) rng() % (r - l + 1);}
double rngesus_d(double l, double r){
    double wow = (double) ((ull) rng()) / ((ull)(0-1));
    return wow * (r - l) + l;
}

template <class T1, class T2>
    bool maximize(T1 &a, T2 b){
        if (a < b) {a = b; return true;}
        return false;
    }

template <class T1, class T2>
    bool minimize(T1 &a, T2 b){
        if (a > b) {a = b; return true;}
        return false;
    }

template <class T>
    void printArr(T container, string separator = " ", string finish = "\n", ostream &out = cout){
        for(auto item: container) out << item << separator;
        out << finish;
    }

template <class T>
    void remove_dup(vector<T> &a){
        sort(ALL(a));
        a.resize(unique(ALL(a)) - a.begin());
    }
#include "longesttrip.h"

//bool are_connected(vector<int> a, vector<int> b){
//    return true;
//}

vector<int> longest_trip(int n, int d){
    vector<int> perm(n);
    for(int i = 0; i < n; ++i) perm[i] = i;

    shuffle(ALL(perm), rng);

    vector<int> S1, S2;
    S1.push_back(perm[0]);

    for(int it = 1; it < n; ++it){
        int i = perm[it];
        vector<int> A = {S1.back()}, B = {i};
        if (are_connected(A, B)) {
            S1.push_back(i);
        }
        else S2.push_back(i);
    }

    if (S1.size() < S2.size()) swap(S1, S2);
    if (S2.empty()) return S1;
    if (!are_connected(S1, S2)) return S1;

    if (!are_connected({S1[0]}, {S1.back()})){
        if (are_connected({S1.back()}, {S2[0]})){
            for(int i: S2) S1.push_back(i);
            return S1;
        }
        else{
            reverse(ALL(S1));
            for(int i: S2) S1.push_back(i);
            return S1;
        }
    }
    if (S2.size() > 1 && !are_connected({S2[0]}, {S2.back()})){
        swap(S1, S2);
        if (are_connected({S1.back()}, {S2[0]})){
            for(int i: S2) S1.push_back(i);
            return S1;
        }
        else{
            reverse(ALL(S1));
            for(int i: S2) S1.push_back(i);
            return S1;
        }
    }

    int l = 0, r = S1.size() - 1;
    while(l < r){
        int mid = (l + r) >> 1;
        vector<int> X;
        for(int i = 0; i <= mid; ++i) X.push_back(S1[i]);

        if (are_connected(X, S2)) r = mid;
        else l = mid + 1;
    }

    int x = l;
    l = 0, r = S2.size() - 1;
    while(l < r){
        int mid = (l + r) >> 1;
        vector<int> X;
        for(int i = 0; i <= mid; ++i) X.push_back(S2[i]);

        if (are_connected({S1[x]}, X)) r = mid;
        else l = mid + 1;
    }

    int y = l;

    vector<int> ans;
    for(int i = 0; i < (int) S1.size(); ++i) ans.push_back(S1[(i + x) % S1.size()]);
    reverse(ALL(ans));
    for(int i = 0; i < (int) S2.size(); ++i) ans.push_back(S2[(i + y) % S2.size()]);
    return ans;
}


//int main(void){
//    ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
//    clock_t start = clock();
//
//    cerr << "Time elapsed: " << clock() - start << "ms!\n";
//    return 0;
//}

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