oj.uz

Submission #840753

# Submission time Handle Problem Language Result Execution time Memory
840753 2023-08-31T16:43:35 Z emeraldblock Longest Trip (IOI23_longesttrip) C++17
15 / 100
 20 ms 308 KB 
#include <bits/stdc++.h>
#include <random>
#include "longesttrip.h"

using namespace std;

vector<int> pi,ip;
bool check(vector<int> a, vector<int> b) {
    for (auto& x : a) x = pi[x];
    for (auto& x : b) x = pi[x];
    return are_connected(a,b);
}

vector<int> isline(vector<int> a) {
    for (auto& x : a) x = pi[x];
#ifdef LOCAL
    for (int i = 1; i < a.size(); ++i) {
        assert(are_connected({a[i-1]}, {a[i]}));
    }
#endif
    return a;
}

mt19937 mt(361);

std::vector<int> longest_trip(int N, int D)
{
    pi.resize(N);
    iota(pi.begin(),pi.end(),0);
    shuffle(pi.begin(),pi.end(),mt);
    vector<int> s1({0}),s2({1});
    bool sep = false;
    for (int i = 2; i < N; ++i) {
        if (check({s1.back()}, {i})) {
            s1.push_back(i);
        } else if (sep || check({s2.back()}, {i})) {
            s2.push_back(i);
            sep = true;
        } else {
            if (false && i < N-1) {
                if (check({i},{i+1})) {
                    while (!s2.empty()) {
                        s1.push_back(s2.back());
                        s2.pop_back();
                    }
                    s2.push_back(i);
                    s2.push_back(i+1);
                } else {
                    s1.push_back(i+1);
                    while (!s2.empty()) {
                        s1.push_back(s2.back());
                        s2.pop_back();
                    }
                    s2.push_back(i);
                }
                ++i;
            } else {
                while (!s2.empty()) {
                    s1.push_back(s2.back());
                    s2.pop_back();
                }
                s2.push_back(i);
            }
        }
    }
    // for (auto x : s1) cerr << x << " ";
    // cerr << "\n";
    // for (auto x : s2) cerr << x << " ";
    // cerr << "\n";
    if (!check(s1, s2)) {
        return isline(s1.size() >= s2.size() ? s1 : s2);
    }
    if (check(s1,{s2.front()})) {
            reverse(s2.begin(),s2.end());
    } else {
        int lo = 0, hi = s2.size();
        while (hi-lo>1) {
            int mid = (lo+hi)/2;
            vector<int> v;
            for (int i = mid; i < hi; ++i) {
                v.push_back(s2[i]);
            }
            if (!check(s1, v)) {
                hi = mid;
            } else {
                lo = mid;
            }
        }
        rotate(s2.begin(),s2.begin()+hi,s2.end());
    }
    if (check({s1.front()},{s2.back()})) {
        reverse(s1.begin(),s1.end());
    } else {
        int lo = 0, hi = s1.size();
        while (hi-lo>1) {
            int mid = (lo+hi)/2;
            vector<int> v;
            for (int i = mid; i < hi; ++i) {
                v.push_back(s1[i]);
            }
            if (!check(v, {s2.back()})) {
                hi = mid;
            } else {
                lo = mid;
            }
        }
        rotate(s1.begin(),s1.begin()+hi,s1.end());
    }
    // for (auto x : s1) cerr << x << " ";
    // cerr << "\n";
    // for (auto x : s2) cerr << x << " ";
    // cerr << "\n";
    while (!s2.empty()) {
        s1.push_back(s2.back());
        s2.pop_back();
    }
    return isline(s1);
}

Subtask #0
0.0 / 0.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 208 KB Output is correct
2 Incorrect 1 ms 308 KB Incorrect
3 Halted 0 ms 0 KB -

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 11 ms 208 KB Output is correct
2 Correct 8 ms 208 KB Output is correct
3 Correct 4 ms 208 KB Output is correct
4 Correct 9 ms 208 KB Output is correct
5 Correct 9 ms 208 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 14 ms 208 KB Output is correct
2 Correct 8 ms 208 KB Output is correct
3 Correct 4 ms 208 KB Output is correct
4 Correct 14 ms 300 KB Output is correct
5 Correct 8 ms 208 KB Output is correct
6 Correct 12 ms 208 KB Output is correct
7 Correct 12 ms 208 KB Output is correct
8 Correct 8 ms 208 KB Output is correct
9 Correct 6 ms 208 KB Output is correct
10 Correct 6 ms 208 KB Output is correct
11 Correct 14 ms 304 KB Output is correct
12 Correct 7 ms 208 KB Output is correct
13 Correct 11 ms 208 KB Output is correct

Subtask #3
0.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 11 ms 208 KB Output is correct
2 Correct 13 ms 208 KB Output is correct
3 Correct 9 ms 208 KB Output is correct
4 Correct 9 ms 208 KB Output is correct
5 Correct 7 ms 208 KB Output is correct
6 Correct 10 ms 208 KB Output is correct
7 Correct 10 ms 208 KB Output is correct
8 Correct 8 ms 208 KB Output is correct
9 Correct 7 ms 208 KB Output is correct
10 Correct 10 ms 208 KB Output is correct
11 Correct 9 ms 208 KB Output is correct
12 Correct 9 ms 208 KB Output is correct
13 Correct 6 ms 208 KB Output is correct
14 Correct 11 ms 208 KB Output is correct
15 Incorrect 5 ms 208 KB Incorrect
16 Halted 0 ms 0 KB -

Subtask #4
0.0 / 60.0

# Verdict Execution time Memory Grader output
1 Correct 11 ms 208 KB Output is correct
2 Correct 10 ms 208 KB Output is correct
3 Correct 10 ms 208 KB Output is correct
4 Correct 9 ms 208 KB Output is correct
5 Correct 7 ms 300 KB Output is correct
6 Correct 20 ms 208 KB Output is correct
7 Correct 12 ms 208 KB Output is correct
8 Correct 10 ms 208 KB Output is correct
9 Correct 10 ms 208 KB Output is correct
10 Correct 11 ms 296 KB Output is correct
11 Correct 13 ms 308 KB Output is correct
12 Correct 10 ms 208 KB Output is correct
13 Correct 5 ms 304 KB Output is correct
14 Correct 16 ms 208 KB Output is correct
15 Incorrect 6 ms 208 KB Incorrect
16 Halted 0 ms 0 KB -