제출 #856401

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
856401		LucaIlie	Unscrambling a Messy Bug (IOI16_messy)	C++17	70 / 100	1 ms	604 KiB

messy

#include "messy.h"
#include <bits/stdc++.h>

using namespace std;

string s0, s1, s;
vector<int> ans;

void divide1( int l, int r, int x ) {
    if ( l > r )
        return;

    int mid = (l + r) / 2;
    for ( int i = l; i <= mid; i++ ) {
        s = s0;
        s[x] = s[mid] = s[i] = '1';
        add_element( s );
    }

    divide1( l, mid - 1, mid );
    divide1( mid + 1, r, mid );
}

void divide2( int l, int r, int x, vector<int> v ) {
    if ( l > r )
        return;

    /*printf( "%d %d\n", l, r );
    for ( int i: v )
        cout << i << " ";
    printf( "\n" );*/

    if ( l == r ) {
        ans[l] = v[0];
        return;
    }

    int mid = (l + r) / 2;

    int p = -1;
    for ( int i: v ) {
        s = s0;
        s[x] = s[i] = '1';
        if ( check_element( s ) )
            p = i;
    }
    ans[mid] = p;
    //printf( "%d\n", p );

    vector<int> leftt, rightt;
    for ( int i: v ) {
        if ( i == p )
            continue;

        s = s0;
        s[x] = s[p] = s[i] = '1';
        if ( check_element( s ) )
            leftt.push_back( i );
        else
            rightt.push_back( i );
    }

    divide2( l, mid - 1, p, leftt );
    divide2( mid + 1, r, p, rightt );
}

vector<int> restore_permutation( int n, int w, int r ) {
    ans.resize( n );
    s0 = s1 = "";
    for ( int i = 0; i < n; i++ ) {
        s0 += '0';
        s1 += '1';
    }

    int mid = (0 + n - 1) / 2;
    divide1( 0, mid - 1, mid );
    divide1( mid + 1, n - 1, mid );
    for ( int i = 0; i < mid; i++ ) {
        s = s1;
        s[i] = '0';
        add_element( s );
    }
    s = s0;
    s[mid] = '1';
    add_element( s );
    compile_set();

    int p;
    vector<int> leftt, rightt;
    for ( int i = 0; i < n; i++ ) {
        s = s0;
        s[i] = '1';
        if ( check_element( s ) ) {
            p = i;
            continue;
        }

        s = s1;
        s[i] = '0';
        if ( check_element( s ) )
            leftt.push_back( i );
        else
            rightt.push_back( i );
    }
    divide2( 0, mid - 1, p, leftt );
    ans[mid] = p;
    divide2( mid + 1, n - 1, p, rightt );

    vector<int> perm( n );
    for ( int i = 0; i < n; i++ )
        perm[ans[i]] = i;

    return perm;
}

컴파일 시 표준 에러 (stderr) 메시지

messy.cpp: In function 'std::vector<int> restore_permutation(int, int, int)':
messy.cpp:107:12: warning: 'p' may be used uninitialized in this function [-Wmaybe-uninitialized]
  107 |     divide2( mid + 1, n - 1, p, rightt );
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 20 / 20
• Subtask 2: 18 / 18
• Subtask 3: 11 / 11
• Subtask 4: 21 / 21
• Subtask 5: 0 / 30