为什么我的数组在每个位置上都以0开头？

所以我是一个初学者。基本上，我的目标是在跳棋游戏开局的位置打印出一块棋盘，但我只能在没有任何棋子的情况下绘制空白棋盘。我不明白为什么，因为我声明只有在数组位置等于白色（-1）时才这样做。但是，如果尝试进行测试并打印出任何随机位置，则每个位置都等于0。因此在这一点上，我感到非常迷茫，因为我编写的代码对我来说是完全有意义的。

//main.cpp
#include <iostream>
#include <array>

#include "board.hpp"

int main()
{
    board Checkers;
    Checkers.printBoard();
}

//board.cpp
class board
{
    private:

        std::array<std::array<int, 8>, 8> boardArr;
        int const white = -1;
        int const black = 0;
        int const player1 = 1;
        int const player2 = 2;


    public:

        board()
        {
            for( int i = 0; i < 8; i++ )
            {
                for( int j = 0; j < 8; j++ )
                {
                    if( ((i + j) % 2)  == 1 )
                    {
                        boardArr.at(i).at(j) = black;
                    }
                    else
                    {
                        boardArr.at(i).at(j) = white;
                    }
                }
            }

            for( int i = 0; i < 3; i++ )
            {
                for( int j = 0; j < 8; j++)
                {
                    if( boardArr.at(i).at(j) = black )
                    {
                        boardArr.at(i).at(j) = player2;
                    }
                }
            }

            for( int i = 5; i < 8; i++ )
            {
                for( int j = 0; j < 8; j++)
                {
                    if( boardArr.at(i).at(j) = black )
                    {
                        boardArr.at(i).at(j) = player1;
                    }
                }
            }
        }

        void printBoard()
        {
            /*
            std::cout << "(TEST) on (white) 0.0::: " << boardArr.at(0).at(0) << "\n\n\n";
            std::cout << "(TEST) on (black) 3.0::: " << boardArr.at(3).at(0) << "\n\n\n";
            std::cout << "(TEST) on (O) 0.1::: " << boardArr.at(0).at(1) << "\n\n\n";
            std::cout << "(TEST) on (X) 7.0::: " << boardArr.at(7).at(0) << "\n\n\n";
            */

            std::cout << "  | A | B | C | D | E | F | G | H |" << "\n"
                      << "--+---+---+---+---+---+---+---+---+--" << "\n";
            for( int i = 0; i < 8; i++ )
            {
                std::cout << -i + 8 << " |";
                for( int j = 0; j < 8; j++ )
                {
                     if( boardArr.at(i).at(j) = white )
                     {
                         std::cout << "   |";
                     }
                     else if( boardArr.at(i).at(j) = black )
                     {
                         std::cout << "###|";
                     }
                     else if( boardArr.at(i).at(j) = player2 )
                     {
                         std::cout << " O |";
                     }
                     else if( boardArr.at(i).at(j) = player1 )
                     {
                        std::cout << " X |";
                     }
                }
                std::cout << "\n" << "--+---+---+---+---+---+---+---+---+--" << "\n";
            }
        }
};