File indexing completed on 2024-04-28 04:05:21

 /*
     SPDX-FileCopyrightText: 2015 Jakob Gruber <jakob.gruber@gmail.com>
 
     SPDX-License-Identifier: GPL-2.0-or-later
 */
 
 #include "boardmap.h"
 
 #include <qglobal.h>
 #include <QRandomGenerator>
 
 static int box_count(const QList<Board::State> &data) {
     int count = 0;
     for (int i = 0; i < data.size(); i++) {
         if (data[i] != Board::Nothing) {
             count++;
         }
     }
     return count;
 }
 
 BoardMap::BoardMap(int width, int height, double box_ratio) :
     Board(width, height), m_box_count(width * height * box_ratio)
 {
     genRandom();
 }
 
 BoardMap::BoardMap(int width, int height, const QList<Board::State> &map) :
     Board(width, height), m_box_count(box_count(map))
 {
     for (int i = 0; i < map.size(); i++) {
         m_state[i] = map[i];
     }
 }
 
 void BoardMap::genRandom() {
     /* To maintain a uniformly random selection of k elements:
      * element i enters the selection with probability k/i. */
 
     QList<int> indices(m_box_count);
     auto *generator = QRandomGenerator::global();
     for (int i = 0; i < m_size; i++) {
         if (i < m_box_count) {
             indices[i] = i;
             continue;
         }
 
         if (generator->bounded(i) <= m_box_count) {
             indices[generator->bounded(indices.size())] = i;
         }
     }
 
     for (int i = 0; i < indices.size(); i++) {
         m_state[indices[i]] = Box;
     }
 }