Submission #840534

# Submission time Handle Problem Language Result Execution time Memory
840534 2023-08-31T13:33:00 Z arbuzick Longest Trip (IOI23_longesttrip) C++17
15 / 100
11 ms 208 KB
#include <bits/stdc++.h>

#include "longesttrip.h"

using namespace std;

vector<int> longest_trip(int n, int d) {
    if (d == 3) {
        vector<int> ans(n);
        iota(ans.begin(), ans.end(), 0);
        return ans;
    }
    if (d == 2) {
        vector<int> ans = {0};
        vector<int> used(n);
        used[0] = 1;
        while (ans.size() < n) {
            int nxt = -1;
            for (int i = 0; i < n; ++i) {
                if (!used[i] && are_connected({ans.back()}, {i})) {
                    nxt = i;
                    used[i] = 1;
                    break;
                }
            }
            if (nxt == -1) {
                reverse(ans.begin(), ans.end());
                for (int i = 0; i < n; ++i) {
                    if (!used[i] && are_connected({ans.back()}, {i})) {
                        nxt = i;
                        used[i] = 1;
                        break;
                    }
                }
            }
            ans.push_back(nxt);
        }
        return ans;
    }
    if (d == 1) {
        vector<int> ans = {0};
        vector<int> used(n);
        used[0] = 1;
        auto try_to_add = [&]() {
            vector<int> vals;
            for (int i = 0; i < n; ++i) {
                if (!used[i]) {
                    vals.push_back(i);
                }
            }
            if (!are_connected({ans.back()}, vals)) {
                return false;
            }
            while (vals.size() > 1) {
                int m = vals.size() / 2;
                vector<int> vals1, vals2;
                for (int i = 0; i < (int)vals.size(); ++i) {
                    if (i < m) {
                        vals1.push_back(vals[i]);
                    } else {
                        vals2.push_back(vals[i]);
                    }
                }
                if (are_connected({ans.back()}, vals1)) {
                    vals = vals1;
                } else {
                    vals = vals2;
                }
            }
            used[vals[0]] = 1;
            ans.push_back(vals[0]);
            return true;
        };
        while (true) {
            if (!try_to_add()) {
                break;
            }
        }
        if (ans.size() < n) {
            reverse(ans.begin(), ans.end());
            if (try_to_add()) {
                while (true) {
                    if (!try_to_add()) {
                        break;
                    }
                }
            } else {
                for (int _ = 0; _ < (int)ans.size(); ++_) {
                    reverse(ans.begin(), ans.end());
                    int vl = ans.back();
                    ans.pop_back();
                    reverse(ans.begin(), ans.end());
                    ans.push_back(vl);
                    if (try_to_add()) {
                        while (true) {
                            if (!try_to_add()) {
                                break;
                            }
                        }
                        break;
                    }
                }
            }
        }
        if (ans.size() * 2 < n) {
            ans.clear();
            for (int i = 0; i < n; ++i) {
                if (!used[i]) {
                    ans.push_back(i);
                }
            }
        }
        return ans;
    }
}

Compilation message

longesttrip.cpp: In function 'std::vector<int> longest_trip(int, int)':
longesttrip.cpp:17:27: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   17 |         while (ans.size() < n) {
      |                ~~~~~~~~~~~^~~
longesttrip.cpp:79:24: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   79 |         if (ans.size() < n) {
      |             ~~~~~~~~~~~^~~
longesttrip.cpp:105:28: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
  105 |         if (ans.size() * 2 < n) {
      |             ~~~~~~~~~~~~~~~^~~
longesttrip.cpp:115:1: warning: control reaches end of non-void function [-Wreturn-type]
  115 | }
      | ^
# Verdict Execution time Memory Grader output
1 Incorrect 0 ms 208 KB invalid array
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 4 ms 208 KB Output is correct
2 Correct 2 ms 208 KB Output is correct
3 Correct 1 ms 208 KB Output is correct
4 Correct 1 ms 208 KB Output is correct
5 Correct 0 ms 208 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 5 ms 208 KB Output is correct
2 Correct 9 ms 208 KB Output is correct
3 Correct 8 ms 208 KB Output is correct
4 Correct 7 ms 208 KB Output is correct
5 Correct 8 ms 208 KB Output is correct
6 Correct 11 ms 208 KB Output is correct
7 Correct 7 ms 208 KB Output is correct
8 Correct 8 ms 208 KB Output is correct
9 Correct 9 ms 208 KB Output is correct
10 Correct 7 ms 208 KB Output is correct
11 Correct 6 ms 208 KB Output is correct
12 Correct 8 ms 208 KB Output is correct
13 Correct 10 ms 208 KB Output is correct
# Verdict Execution time Memory Grader output
1 Incorrect 0 ms 208 KB invalid array
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 0 ms 208 KB invalid array
2 Halted 0 ms 0 KB -