如何设置具有随机字符的二维字符数组？

Question

我正在解决一个问题，我试图获取一定百分比的字符并使用 Math.random 将它们随机填充到 5x5 数组中，以在二维数组中存储 25 个项目。我现在想出了这个，但我不明白为什么它没有填充我想要的字符。它只是在做“X”而不是随机的，它似乎与 X 的总数是一致的。我试图输出 X、O 的百分比以及剩下的空白。它只输出 10 个 X，它们似乎不是随机的。如果我能得到任何关于为什么会发生这种情况的建议，我将不胜感激。

public static void main(String []args){

        char [][] tissue = new char [5][5];

        assignCellTypes(tissue,40,40);

    }

    public static void assignCellTypes(char[][] tissue,int percentO, int percentX){


                double cellx=0.0;
                double cellO=0.0;
                double totalO=0;
                double totalX = 0;
                totalO = (double)percentO/100;


                totalX = (double)
                        percentX/100;

                        cellx = totalX *(tissue.length*tissue.length);
                        cellO = totalO *(tissue.length*tissue.length);

            int i;
            int j ;
        for(int row = 0;row<tissue.length;row++){
            for(int col = 0;col<tissue[row].length;col++){


                    if(cellx>0){
                        i = (int)Math.floor(Math.random()*tissue.length);
                        j = (int)Math.floor(Math.random()*tissue.length);

                        tissue[i][j] = 'X';
                        System.out.print(tissue[i][j] + "  ");

                        cellx--;

                        if(cellO>0 && tissue[i][j] != 'X' ){
                            i = (int)Math.floor(Math.random()*tissue.length);
                            j = (int)Math.floor(Math.random()*tissue.length);

                            tissue[i][j] = 'O';
                            System.out.print(tissue[i][j] + "  ");
                            cellO--;

                    if(tissue[i][j] != 'X' && tissue[i][j] != 'O'){

                        tissue[i][j] = ' ';

                        System.out.print(tissue[i][j] + "  ");

                    }
                        }



                    }


            }
            System.out.println();
        }


    }
}

Answer 1

我不完全知道您要归档什么，但您似乎只是想用 X 和 O 随机填充一个 char 数组以及一个机会因素，在这种情况下有很多更简单的解决方案

public static void assignCellTypes(char[][] tissue, int percentO, int percentX)
{
    double chanceO = percentO / (double) ( percentO + percentX );

    Random r = new Random(); //java.util.Random

    for(int i=0; i < tissue.length; i++)
        for(int j=0; j < tissue[i].length; j++)
            if( r.nextDouble() <= chanceO )
                tissue[i][j] = 'O';
            else
                tissue[i][j] = 'X';
}

编辑@comment，我认为这是您想要实现的目标：

public static void assignCellTypes(char[][] tissue, int percentO, int percentX)
{
    if(percentO + percentX > 100)
        throw new Exception("You can't have more than 100%!");

    double chanceO = percentO/100d;
    double chanceX = percentX/100d;

    Random r = new Random(); //java.util.Random

    for(int i=0; i < tissue.length; i++)
        for(int j=0; j < tissue[i].length; j++)
        {
            double random = r.nextDouble();

            if( random <= chanceO )
                tissue[i][j] = 'O';
            else if( random <= chanceO + chanceX )
                tissue[i][j] = 'X';
        }
}