Question

所以...我想做一个2D选择排序algorythm，但我不知道我做错了什么（C），你能帮帮我吗？

我只需要从第一个数组复制偶数数字到第二个数组，然后通过选择排序对它们进行排序，通常是：

for(x = 0; x < maxlength - 1; x++)
    for(y = x + 1; y < maxlength; y++)
    {
         if(arr[a] > arr[b]
             temp = arr[a];
             arr[a] = arr[b];
             arr[b] = temp;
    }

事情就是我无法将其转化为2D 这是代码：

void arrcpy(int arrA[3][5], int arrB[3][5])
{
    int countx, county;
    int countxB = 0, countyB = 0;
    int temp;
    int tempx, tempy;
    int swapped = 0;

    for(countx = 0; countx < 3; countx++)
    {
        for(county = 0; county < 5; county++)
            if(arrA[countx][county] % 2 == 0 && arrA[countx][county] != 0)
            {
                arrB[countxB][countyB] = arrA[countx][county];
                if((countyB) / 4 == 1)
                {
                    countxB++;
                    countyB = 0;
                }
                else
                    countyB++;
            }
    }

    printf("\n");
    show(arrB);
    printf("\n");
    //Works up to now

    for(countx = 0; countx < 3; countx++)
        for(county = 0; county < 5; county++)
            if(arrB[countx][county] % 2 == 0)
            {
                tempx = countx;
                tempy = county;
            }

    countx = county = countxB = 0;
    countyB = 1;
    //Works up to now

    for(countx = 0; countx < 3; countx++)
    {
        for(county = 0; county < 5; county++)
        {
            swapped = 0;
            for(countxB = 0; countxB < 3; countxB++)
            {
                if(swapped)
                    break;

                for(countyB = 0; countyB < 5; countyB++)
                {
                    if(swapped)
                        break;
                    if(arrB[countx][county] < arrB[countxB][countyB])
                    {
                        temp = arrB[countx][county];
                        arrB[countx][county] = arrB[countxB][countyB];
                        arrB[countxB][countyB] = temp;
                        swapped = 1;
                    }
                }
            }
        }
    }
}

Answer 1

坦率地说，我很难按照你的代码。部分原因是由于不幸的长名选择。我在这里分享Pablo情绪。通常，选择短名称i，j进行索引。

请允许我说，应该以可以重用函数的方式编写程序。读取和调试代码的一小部分更容易。 main函数应尽可能短。它应该只调用已经准备好的函数。

借助1D阵列对2D阵列进行排序在概念上比在适当的位置更简单。我也添加了这个解决方案。

您可能需要查看：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define ROW 3
#define COL 5 

void arrcpy(int arrA[ROW][COL], int arrB[ROW][COL])
{
   // copy from arrA to arrB ( arrA -> arrB )
   // copy only even numbers from the first to the second array but not 0   
    int i, j;

    for(i = 0; i < ROW; i++)
    {
        for(j = 0; j < COL; j++)

            if(arrA[i][j] % 2 == 0 && arrA[i][j] != 0)
            {
                arrB[i][j] = arrA[i][j];
            }
    }
}

void show(char *mess, int arr[ROW][COL], int row, int col )
 {
    int i;
    int j;

    printf("%s\n", mess);

    for(i=0 ;i<row; i++)
    {
        for(j=0; j<col; j++)
            printf("%d ",arr[i][j]);

        printf("\n");
    }
    printf("\n");
 }

void sort(int arr[ROW][COL], int row, int col)
{
    int min,i,j,tmp,y,k,w;
    int z=0, q=0;

    for(i=0; i<ROW; i++)
    {
        for(j=0; j<COL; j++)
        {
            z = i;
            q = j;

            min = arr[i][j];
            w = j;

            for(k=i; k<ROW; k++)
            {
                for(; w<COL; w++)
                {
                    if(arr[k][w] < min)
                    {
                        min = arr[k][w];

                        z = k;
                        q = w;
                    }
                }
                w = 0;
            }

            tmp = arr[i][j];

            arr[i][j] = min;
            arr[z][q] = tmp;
        }
    }
}

//-------------------------------
void convert2Dto1D(int arr[ROW*COL], int matrix[ROW][COL], int row, int col)
{
    // convert 2D array into 1D array     
    int k=0;
    for(int i=0; i<row;i++){
       for(int j=0; j<col; j++){
         arr[k++] = matrix[i][j];
       } 
    }
}  

void convert1Dto2D(int matrix[ROW][COL], int arr[ROW*COL], int row, int col)
{
    // convert 1D array into 2D array  
    memcpy(matrix, arr, row*col * sizeof(int));
}

void sort1D(int arr[ROW*COL], int row, int col )
{
   // sort  1D array       
   int temp;

   for(int i=0; i<row*col; i++)
   {
        for(int j=0; j<row*col-1; j++)
        {
           if(arr[j] > arr[j+1]){

                temp = arr[j];
                arr[j] = arr[j+1];
                arr[j+1] = temp;
            }
        }
    }
}
//---------------------------------------------------- 

int main()
{
    int arrA[ROW][COL] = {{9,8,2,10,14},{4,5,1,11,0},{6,7,3,12,0}};
    int arrB[ROW][COL] = {{19,18,12,110,114},{14,15,11,111,115},{161,17,13,112,113}};

    show("arrA:\n", arrA, ROW, COL );
    show("arrB:\n", arrB, ROW, COL );

    arrcpy(arrA, arrB);

    show("Arr B after copy:\n",   arrB, ROW, COL );

    sort(arrB, ROW, COL) ;

    show("ArrB after sorting:\n", arrB, ROW, COL );

    // Sorting using 1D array  
    int arr[ROW][COL] =  {{9,8,2,10,14},{4,5,1,11,0},{6,7,3,12,0}};
    show("--------------------\nArray to be sorted:\n", arr, ROW, COL );
    int result[ROW*COL];

    convert2Dto1D(result, arr, ROW, COL);
    sort1D(result, ROW, COL );
    convert1Dto2D(arr, result, ROW, COL);
    show("Sorted array:\n", arr, ROW, COL );

    return 0;
}

输出：

arrA:

9 8 2 10 14 
4 5 1 11 0 
6 7 3 12 0 

arrB:

19 18 12 110 114 
14 15 11 111 115 
161 17 13 112 113 

Arr B after copy:

19 8 2 10 14 
4 15 11 111 115 
6 17 13 12 113 

ArrB after sorting:

2 4 6 8 10 
11 12 13 14 15 
17 19 111 113 115 

--------------------
Array to be sorted:

9 8 2 10 14 
4 5 1 11 0 
6 7 3 12 0 

Sorted array:

0 0 1 2 3 
4 5 6 7 8 
9 10 11 12 14

我希望它有所帮助。

2D阵列选择排序

1 个答案: