oj.uz

Submission #840755

# Submission time Handle Problem Language Result Execution time Memory
840755 2023-08-31T16:43:47 Z emeraldblock Longest Trip (IOI23_longesttrip) C++17
15 / 100
 17 ms 336 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 (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 3 ms 208 KB Incorrect
3 Halted 0 ms 0 KB -

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 17 ms 260 KB Output is correct
2 Correct 9 ms 208 KB Output is correct
3 Correct 9 ms 208 KB Output is correct
4 Correct 10 ms 208 KB Output is correct
5 Correct 10 ms 208 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 9 ms 208 KB Output is correct
2 Correct 7 ms 256 KB Output is correct
3 Correct 13 ms 208 KB Output is correct
4 Correct 10 ms 208 KB Output is correct
5 Correct 11 ms 336 KB Output is correct
6 Correct 15 ms 208 KB Output is correct
7 Correct 13 ms 208 KB Output is correct
8 Correct 7 ms 208 KB Output is correct
9 Correct 8 ms 208 KB Output is correct
10 Correct 8 ms 208 KB Output is correct
11 Correct 7 ms 308 KB Output is correct
12 Correct 8 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 13 ms 208 KB Output is correct
2 Correct 11 ms 208 KB Output is correct
3 Correct 10 ms 208 KB Output is correct
4 Correct 10 ms 208 KB Output is correct
5 Correct 8 ms 208 KB Output is correct
6 Correct 15 ms 208 KB Output is correct
7 Correct 11 ms 208 KB Output is correct
8 Correct 9 ms 208 KB Output is correct
9 Correct 11 ms 256 KB Output is correct
10 Correct 7 ms 208 KB Output is correct
11 Correct 12 ms 208 KB Output is correct
12 Correct 9 ms 208 KB Output is correct
13 Correct 9 ms 208 KB Output is correct
14 Correct 9 ms 208 KB Output is correct
15 Incorrect 4 ms 208 KB Incorrect
16 Halted 0 ms 0 KB -

Subtask #4
0.0 / 60.0

# Verdict Execution time Memory Grader output
1 Correct 15 ms 208 KB Output is correct
2 Correct 8 ms 208 KB Output is correct
3 Correct 9 ms 208 KB Output is correct
4 Correct 7 ms 256 KB Output is correct
5 Correct 9 ms 208 KB Output is correct
6 Correct 14 ms 240 KB Output is correct
7 Correct 13 ms 256 KB Output is correct
8 Correct 13 ms 208 KB Output is correct
9 Correct 11 ms 208 KB Output is correct
10 Correct 12 ms 300 KB Output is correct
11 Correct 8 ms 304 KB Output is correct
12 Correct 7 ms 208 KB Output is correct
13 Correct 13 ms 208 KB Output is correct
14 Correct 10 ms 208 KB Output is correct
15 Incorrect 5 ms 208 KB Incorrect
16 Halted 0 ms 0 KB -