oj.uz

Submission #848627

# Submission time Handle Problem Language Result Execution time Memory
848627 2023-09-13T06:12:57 Z piOOE Longest Trip (IOI23_longesttrip) C++17
5 / 100
 16 ms 600 KB 
#include "longesttrip.h"
#include <bits/stdc++.h>

using namespace std;

std::vector<int> longest_trip(int N, int D) {
    mt19937 rnd(228);

    vector<int> a, b, ord(N);
    iota(ord.begin(), ord.end(), 0);
    shuffle(ord.begin(), ord.end(), rnd);
    int known = -1;

    for (int x : ord) {
        if (a.empty() || b.empty()) {
            (a.empty() ? a : b).push_back(x);
            continue;
        }
        if (rnd() % 2) {
            swap(a, b);
        }
        if (1) {
            int res = are_connected({a.back()}, {x});
            if (res == 1) {
                a.push_back(x);
                known = -1;
            } else if (known != -1) {
                if (known == 1) { // unreachable
                    a.insert(a.end(), b.rbegin(), b.rend());
                    b = {x};
                    known = -1;
                } else {
                    b.push_back(x);
                    known = 0;
                }
            } else {
                res = are_connected({b.back()}, {x});
                if (res == 0) {
                    a.insert(a.end(), b.rbegin(), b.rend());
                    b = {x};
                    known = -1;
                } else {
                    b.push_back(x);
                    known = 0;
                }
            }
        } else {
            if (are_connected({a.back()}, {x})) {
                a.push_back(x);
            } else if (are_connected({b.back()}, {x})) {
                b.push_back(x);
            } else {
                a.insert(a.end(), b.rbegin(), b.rend());
                b = {x};
            }
        }
    }

    if (a.empty() || b.empty() || !are_connected(a, b)) {
        return a.size() > b.size() ? a : b;
    }

    if (size(a) < size(b)) {
        swap(a, b);
    }

    if (!are_connected(a, {b[0]})) {
        int lo = 0, hi = size(b);
        while (lo + 1 < hi) {
            int mid = lo + hi >> 1;
            if (are_connected(a, vector(b.begin(), b.begin() + mid))) {
                hi = mid;
            } else {
                lo = mid;
            }
        }
        rotate(b.begin(), b.begin() + lo, b.end());
    }

    assert(are_connected(a, {b[0]}));
    
    int lo = 0, hi = size(a);
    while (lo + 1 < hi) {
        int mid = lo + hi >> 1;
        if (are_connected(vector(a.begin(), a.begin() + mid), {b[0]})) {
            hi = mid;
        } else {
            lo = mid;
        }
    }
    rotate(a.begin(), a.begin() + hi, a.end());
    a.insert(a.end(), b.begin(), b.end());
    return a;
}

Compilation message

longesttrip.cpp: In function 'std::vector<int> longest_trip(int, int)':
longesttrip.cpp:70:26: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   70 |             int mid = lo + hi >> 1;
      |                       ~~~^~~~
longesttrip.cpp:84:22: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   84 |         int mid = lo + hi >> 1;
      |                   ~~~^~~~

Subtask #0
0.0 / 0.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 2 ms 448 KB Output is correct

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 11 ms 344 KB Output is correct
2 Correct 7 ms 344 KB Output is correct
3 Correct 7 ms 344 KB Output is correct
4 Correct 5 ms 344 KB Output is correct
5 Correct 5 ms 600 KB Output is correct

Subtask #2
0.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 11 ms 344 KB Output is correct
2 Correct 7 ms 344 KB Output is correct
3 Correct 5 ms 344 KB Output is correct
4 Correct 5 ms 344 KB Output is correct
5 Correct 5 ms 344 KB Output is correct
6 Correct 16 ms 344 KB Output is correct
7 Incorrect 2 ms 344 KB Incorrect
8 Halted 0 ms 0 KB -

Subtask #3
0.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 11 ms 344 KB Output is correct
2 Correct 7 ms 344 KB Output is correct
3 Correct 5 ms 344 KB Output is correct
4 Correct 5 ms 344 KB Output is correct
5 Correct 5 ms 344 KB Output is correct
6 Correct 13 ms 344 KB Output is correct
7 Incorrect 2 ms 344 KB Incorrect
8 Halted 0 ms 0 KB -

Subtask #4
0.0 / 60.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 344 KB Output is correct
2 Correct 8 ms 344 KB Output is correct
3 Correct 5 ms 344 KB Output is correct
4 Correct 6 ms 344 KB Output is correct
5 Correct 5 ms 496 KB Output is correct
6 Correct 12 ms 344 KB Output is correct
7 Incorrect 2 ms 344 KB Incorrect
8 Halted 0 ms 0 KB -