C

时间:2019-02-05 18:05:54

标签: c arrays sorting shuffle

我必须解决以下问题:

以下不完整的代码说明了一个程序,该程序由包含16个已排序名称的数组组成。程序的最后部分在屏幕上显示这些名称。您需要在标有空矩形的部分中编写代码,以便对名称进行重新排序。输出名称时,不应以升序输出,而是以随机顺序输出。您只需要在检查脚本中编写缺少的代码,而不是整个程序。

如何以最简单/直观的方式编写此代码?

#include <stdio.h>
#include <time.h>
int main(void)
{
    int i, j, k;
    char temp[20];
    char names[16][20] = { "Anne" , "Carmen" , "David" , "Jesmond" ,
    "John" , "Joseph" , "Karen" , "Kevin" ,
    "Manuel" , "Maria" , "Matthew" , "Michaela" ,
    "Paul" , "Sandra" , "William" , "Yilenia" };

    //--------------------------- The Code between the dotted lines is the one I still need to write -----------------
    char randomnames[16][20];
    srand(time(NULL));
    for (i = 0; i < 16; i++)
    {
        j = rand() % 17;
        printf("%d\n", j);
        randomnames[i] = names[j];
    }
    //---------------------------------------------------------------------------


    for (i = 0; i < 16; i++)
    {
        puts(randomnames[i]);
    }
    getchar();
    return 0;

}

1 个答案:

答案 0 :(得分:1)

拥有

char names[16][20] = ...;
char randomnames[16][20];

你不能做

randomnames[i] = names[j];

但是

char names[16][20] = ...;
char * randomnames[16];
...
randomnames[i] = names[j];

char names[16][20] = ...;
char randomnames[16][20];
...
strcpy(randomnames[i], names[j]);

警告,当我看到问题的第一个版本时,您必须打印名称而不是 randomnames ,这意味着您需要修改 randomnames 并且char temp[20]清楚地表明您必须在随机名称

中交换名称

是这样的:

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

int main(void)
{
  int i, j, k;
  char temp[20];
  char names[16][20] = { "Anne" , "Carmen" , "David" , "Jesmond" ,
                         "John" , "Joseph" , "Karen" , "Kevin" ,
                         "Manuel" , "Maria" , "Matthew" , "Michaela" ,
                         "Paul" , "Sandra" , "William" , "Yilenia" };

  //--------------------------- The Code between the dotted lines is the one I still need to write -----------------
  srand(time(NULL));

  for (i = 0; i < 16; i++) /* can be an other number of loop */
  {
    j = rand() % 17;
    k = rand() % 17;
    if (j != k) {
      strcpy(temp, names[j]);
      strcpy(names[j], names[k]);
      strcpy(names[k], temp);
    }
  }
  //---------------------------------------------------------------------------

  for (i = 0; i < 16; i++)
  {
    puts(names[i]);
  }
  getchar();
  return 0;
}

如您所见,我使用了所有变量,没有其他变量。

编译和执行示例:

pi@raspberrypi:~ $ gcc -pedantic -Wall s.c
pi@raspberrypi:~ $ ./a.out
Sandra
John
William
Karen
Joseph
Kevin
Manuel
Carmen
Anne
Jesmond
Michaela
Maria
Paul
Matthew
David
Yilenia