Question

我一整天都在研究这个问题，但是找不到下一步该做什么。我有它排序行，但它不会完全排序最后一行。这是我的代码。我知道一旦我或某人得到这个，我会感到愚蠢。谢谢你

    public class Sort2DRow
{
   public static void main (String [] args)
   {
      int[][] matrix = {{3,5,6}, {4,1,2},{9,8,7}};

      System.out.println("Before the sort");
      for(int row = 0; row <matrix.length; row++){
         for(int col = 0; col <matrix[row].length; col++){
            System.out.print(matrix[row][col] + " ");
         }
         System.out.println();
      }

      System.out.println();//Spacer
      System.out.println("After sort method");
      sortRow(matrix);

   }

   public static int[][] sortRow(int[][] m)
   {
      int temp = 0;
      for(int row = 0; row < m.length ; row++)
      {
         for(int col = 0; col < m.length -1; col++){
            if(m[row][col] > m[row][col + 1])
            {
               temp = m[row][col];
               m[row][col] = m[row][col + 1];
               m[row][col + 1] = temp;
            }
         }
       }

       for(int row = 0; row <m.length; row++){
         for(int col = 0; col <m[row].length; col++){
            System.out.print(m[row][col] + " ");
         }
         System.out.println();
      }

       int[][] result = m;
       return result;
   }

}

Answer 1

你走在正确的轨道上，但问题是你错误地认为for(int row = 0; row < m.length ; row++)是你的外部气泡循环。它实际上只是“加载”2-d数组中下一行的循环。所以你需要添加缺少的循环：

for(int col = 0; col < m[row].length; col++){ //This is the real outer bubblesort loop. Change it to m[row].length
    for(int nextCol = col; nextCol < m[row].length; nextCol++) {
        if(m[row][col] > m[row][nextCol])
        {
           temp = //I'll let you figure this out
           m[row][col] = //....
           m[row][nextCol] = //...
        }
     }
}

Answer 2

最终代码产品

public class Sort2DRowTest
{
   public static void main (String [] args)
   {
      int[][] matrix = {{3,5,6}, {4,1,2},{9,8,7}};

      System.out.println("Before the sort");
      for(int row = 0; row <matrix.length; row++){
         for(int col = 0; col <matrix[row].length; col++){
            System.out.print(matrix[row][col] + " ");
         }
         System.out.println();
      }

      System.out.println();//Spacer
      System.out.println("Sort method");
      sortRow(matrix);

      System.out.println();//Spacer
      System.out.println("After the sort");
      for(int row = 0; row <matrix.length; row++){
         for(int col = 0; col <matrix[row].length; col++){
            System.out.print(matrix[row][col] + " ");
         }
         System.out.println();
      }

   }

   public static int[][] sortRow(int[][] m)
   {

      int[][] result = new int[m.length][m[0].length];

    // Copy from m to result
       for (int i = 0; i < m.length; i++)
         for (int j = 0; j < m[0].length; j++)
        result[i][j] = m[i][j];

      int temp = 0;
      for(int row = 0; row < result.length ; row++)
      {
         for(int col = 0; col < result[row].length; col++){ //This is the real outer bubblesort loop. Change it to m[row].length
            for(int nextCol = col; nextCol < result[row].length; nextCol++) {
               if(result[row][col] > result[row][nextCol])
               {
                  temp = result[row][col];
                  result[row][col] = result[row][nextCol];
                  result[row][nextCol] = temp;
               }
            }
            System.out.print(result[row][col] + " ");
         }
         System.out.println();
       }
       //int[][] result = m;
       return result;
   }

}

实现以下方法以对二维数组中的行进行排序

2 个答案: