Submission #388822

#	Time	Username	Problem	Language	Result	Execution time	Memory
388822		ParsaAlizadeh	Unscrambling a Messy Bug (IOI16_messy)	C++17	100 / 100	3 ms	472 KiB

messy

#include <bits/stdc++.h>
#include "messy.h"
using namespace std;

string to_string(vector<bool> const& mask) {
    string res;
    for (bool b : mask)
        res.push_back(b ? '1' : '0');
    return res;
}

void insert(int l, int r, vector<bool>& mask) {
    if (r - l == 1)
        return;
    int mid = (l + r) >> 1;
    for (int i = l; i < mid; i++) {
        mask[i] = true;
        add_element(to_string(mask));
        mask[i] = false;
    }
    for (int i = mid; i < r; i++)
        mask[i] = true;
    insert(l, mid, mask);
    for (int i = l; i < r; i++)
        mask[i] = i < mid;
    insert(mid, r, mask);
    for (int i = l; i < mid; i++)
        mask[i] = false;
}

void solve(int l, int r, vector<bool>& mask, vector<int>& perm) {
    if (r - l == 1) {
        int ind;
        for (int i = 0; i < mask.size(); i++)
            if (!mask[i])
                ind = i;
        perm[ind] = l;
        return;
    }
    vector<int> lft, rgt;
    for (int i = 0; i < mask.size(); i++) {
        if (!mask[i]) {
            mask[i] = true;
            (check_element(to_string(mask)) ? lft : rgt).push_back(i);
            mask[i] = false;
        }
    }
    int mid = (l + r) >> 1;
    for (int i : rgt)
        mask[i] = true;
    solve(l, mid, mask, perm);
    for (int i : lft)
        mask[i] = true;
    for (int i : rgt)
        mask[i] = false;
    solve(mid, r, mask, perm);
    for (int i : lft)
        mask[i] = false;
}

vector<int> restore_permutation(int n, int w, int r) {
    vector<bool> mask(n, false);
    insert(0, n, mask);
    compile_set();
    vector<int> perm(n);
    solve(0, n, mask, perm);
    return perm;
}

Compilation message (stderr)

messy.cpp: In function 'void solve(int, int, std::vector<bool>&, std::vector<int>&)':
messy.cpp:34:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<bool>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   34 |         for (int i = 0; i < mask.size(); i++)
      |                         ~~^~~~~~~~~~~~~
messy.cpp:41:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<bool>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   41 |     for (int i = 0; i < mask.size(); i++) {
      |                     ~~^~~~~~~~~~~~~
messy.cpp:37:17: warning: 'ind' may be used uninitialized in this function [-Wmaybe-uninitialized]
   37 |         perm[ind] = l;
      |                 ^

• Subtask 1: 20 / 20
• Subtask 2: 18 / 18
• Subtask 3: 11 / 11
• Subtask 4: 21 / 21
• Subtask 5: 30 / 30