稀疏数组

普通二维数组压缩成稀疏数组保存成文件，再从文件中读取稀疏数组，将其解析成普通二维数组
package sparse;

import java.io.*;
import java.util.ArrayList;
import java.util.List;

public class SpareArray {

public static void main(String[] args) throws IOException {

    //创建一个原始的二维数组
    //0表示没有棋子，1表示黑子，2表示白子
    int chessArr1[][] = new int[11][11];
    chessArr1[1][2] = 1;
    chessArr1[2][3] = 2;
    chessArr1[3][4] = 1;
    PrintUtil.printMethod(chessArr1);

    //转为稀疏数组
    //1.统计有效数据的个数
    int sum = 0;
    for (int i = 0;i < chessArr1.length;i++){
        for (int j = 0;j < chessArr1[i].length; j++){

            if (chessArr1[i][j] != 0){
                sum++;
            }
        }
    }
    //2.创建稀疏数组并初始化第一行
    int sparseArr[][] = new int[sum+1][3];
    sparseArr[0] = new int[]{11, 11, sum};
    //3.赋值其他行
    int count = 0;
    for (int i = 0;i < chessArr1.length;i++){
        for (int j = 0;j < chessArr1[i].length; j++){

            if (chessArr1[i][j] != 0){
                count++;
                sparseArr[count][0] = i;
                sparseArr[count][1] = j;
                sparseArr[count][2] = chessArr1[i][j];
            }
        }
    }
    //输出并存到文件中
    File file = new File("D:/result/array/test01.txt");
    FileWriter fw  = new FileWriter(file);
    for (int[] row : sparseArr){
        for (int data : row){
            System.out.print(data + "\t");
            fw.write(data + "\t");
        }
        System.out.println();
        fw.write("\n");
    }
    fw.close();

    //从文件中读取稀疏数组
    BufferedReader br = new BufferedReader(new FileReader(file));
    String line;
    List<Integer> list = new ArrayList();
    int row = 0,column = 0;
    while ((line= br.readLine()) != null){
        String[] temp = line.split("\t");
        for (int i=0; i<temp.length; i++){
            list.add(Integer.valueOf(temp[i]));
        }
        column = temp.length;
        row++;
    }
    br.close();
    int[][] sparseArr2 = new int[row][column];
    int count2 = 0;
    for (int i=0; i<row; i++){
        for (int j=0; j<column; j++){
            sparseArr2[i][j] = list.get(count2);
            count2++;
        }
    }
    //转为二维数组
    int row2 = sparseArr2[0][0];
    int column2 = sparseArr2[0][1];
    int[][] chessArr2 = new int[row2][column2];
    for (int i=1; i<sparseArr2[0][2] + 1; i++){
        row2 = sparseArr2[i][0];
        column2 = sparseArr2[i][1];
        chessArr2[row2][column2] = sparseArr2[i][2];
    }
    PrintUtil.printMethod(chessArr2);
}

}
package sparse;

public class PrintUtil {

public static void printMethod(int[][] srcArray){
    for(int[] rowCount : srcArray){//遍历二维数组的每一行
        for (int data : rowCount){
            System.out.print(data + "\t");
        }
        System.out.println();
    }
}

}

标签：int,chessArr1,稀疏,++,数组,sparseArr,new
来源： https://blog.csdn.net/weixin_42523683/article/details/111360580