Submission #1011203

#	Time	Username	Problem	Language	Result	Execution time	Memory
1011203		boris_mihov	Mechanical Doll (IOI18_doll)	C++17	37 / 100	58 ms	13356 KiB

doll

#include "doll.h"
#include <algorithm>
#include <iostream>
#include <numeric>
#include <cassert>
#include <vector>

typedef long long llong;
const int MAXN = 400000 + 10;
const int INF  = 1e9;

int n, m, cnt;
std::vector <int> order;
std::vector <int> prefix;
std::vector <int> a, c, x, y;

int reversed(int num, int bits)
{
    int res = 0;
    for (int i = 0 ; i < bits ; ++i)
    {
        if (num & (1 << i))
        {
            res |= (1 << bits - i - 1);
        }
    }

    return res;
}

void rec(int l, int r, int node)
{
    if (prefix[r] - (l == 0 ? 0 : prefix[l - 1]) == 0)
    {
        x[node - 1] = -node;
        y[node - 1] = -1;
        return;
    }

    int mid = l + r >> 1;
    if (l != mid)
    {
        x[node - 1] = -(++cnt);
        rec(l, mid, -x[node - 1]);
    } else
    {
        x[node - 1] = order[l];
    }

    if (mid + 1 != r)
    {
        y[node - 1] = -(++cnt);
        rec(mid + 1, r, -y[node - 1]);
    } else
    {
        y[node - 1] = order[r];
    }
}

void create_circuit(int M, std::vector <int> A)
{
    a = A;
    m = M;
    a.push_back(0);
    int bits = 0;
    int n = a.size();
    while ((1 << bits) < n)
    {
        bits++;
    }

    order.resize(1 << bits, -1);
    prefix.resize(1 << bits);
    for (int i = 0 ; i < n - 1 ; ++i)
    {
        order[reversed(i, bits)] = a[i];
    }

    order[(1 << bits) - 1] = 0;
    prefix[0] = (order[0] != -1);
    for (int i = 1 ; i < (1 << bits) ; ++i)
    {
        prefix[i] = prefix[i - 1] + (order[i] != -1);
    }

    x.resize(1 << bits);
    c.resize(m + 1);
    y.resize(1 << bits);
    c[0] = -(++cnt);
    for (int i = 1 ; i <= m ; ++i)
    {
        c[i] = -1;
    }

    rec(0, (1 << bits) - 1, 1);
    answer(c, x, y);

    while (x.size() > cnt)
    {
        x.pop_back();
        y.pop_back();
    }
}

Compilation message (stderr)

doll.cpp: In function 'int reversed(int, int)':
doll.cpp:24:35: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
   24 |             res |= (1 << bits - i - 1);
      |                          ~~~~~~~~~^~~
doll.cpp: In function 'void rec(int, int, int)':
doll.cpp:40:17: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   40 |     int mid = l + r >> 1;
      |               ~~^~~
doll.cpp: In function 'void create_circuit(int, std::vector<int>)':
doll.cpp:98:21: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   98 |     while (x.size() > cnt)
      |            ~~~~~~~~~^~~~~

• Subtask 1: 0 / 2
• Subtask 2: 0 / 4
• Subtask 3: 0 / 10
• Subtask 4: 0 / 10
• Subtask 5: 9 / 18
• Subtask 6: 28 / 56