c - 我的程序中收到一些未报告的值

Question

我的程序是要求用户输入其组中人员的姓名和年龄。在程序开始时用户并不知道人数。用户继续输入数据直到用户输入年龄零。程序最终打印出平均年龄。

源码如下

#include<stdio.h>
#include<stdlib.h>
#include<math.h>
typedef struct group {
    char user_Name[21];
    int user_age;
}Group;
int main()
{
    Group  *REC1;
    FILE *out_file, *read_file;
    int count_age=0, age, sum_age, i;
    float avg_age;
    char name[21]="", str[21]= "details.txt";
    char sample_chr;
    //opening a file in writing mode
      out_file = fopen(str, "a");

    // test for files not existing. 
       if (out_file == NULL) 
       {   
           printf("Error! Could not open file\n"); 
           exit(-1); // must include stdlib.h 
       }

       printf("\nEnter the Details of the person:\n\n");
       do
       {
         printf("Enter the User Name:\n");
         fflush(stdin);
         scanf("%[^\n]",name);

         printf("Enter the Age:\n");
         fflush(stdin);
         scanf("%d",&age);


         if(age == 0)
         {
            break;

         }
         else
         {
            // write to file 
            fprintf(out_file,"%s,%d\n", name, age);
         }

       }while(1);

       read_file = fopen(str,"r");
            //counting the number of lines present in the above file
             sample_chr = getc(read_file);
             while (sample_chr != EOF)
             {
                if (sample_chr == '\n')
                   count_age = count_age +1;

               sample_chr = getc(read_file);
             }             
             rewind(read_file);

             //allocating space for array of structure dynamically
             printf("\n%d\n",count_age);
            count_age = count_age - 1;
             REC1  =  (Group*)malloc(count_age*sizeof(Group));

             //storing the values in array of structures
             for(i=0; i<=count_age; i++)
                fscanf(read_file, "%s,%d", REC1[i].user_Name, &REC1[i].user_age);


             fclose(read_file);
             fclose(out_file);
             for(i =0; i<=count_age; i++)
             printf("\n%s %d\n", REC1[i].user_Name, REC1[i].user_age);

             for(i=0, sum_age=0; i<=count_age; i++)
              sum_age = sum_age + REC1[i].user_age;

             avg_age =  (float)sum_age/(count_age);

            printf("\n\nThe average age is %f\n\n\n", avg_age); 



    system("pause");
    return 0;

}

当我编译时，它没有显示任何错误。当我运行时，它显示 exe 文件停止工作。

Answer 1

以下内容正在运行

必须更改 name[] 的 scanf() 中的格式 ( http://www.cplusplus.com/reference/cstdio/scanf/ )

，必须移动 fclose(out_file) 并且必须更改 while 循环的结束条件...

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

typedef struct group {
    char user_Name[21];
    int user_age;
}Group;

int main()
{
    Group  *REC1;
    FILE *out_file, *read_file;
    int count_age=0, age, sum_age, i;
    float avg_age;
    char name[21]="", str[21]= "details.txt";
    char sample_chr;
    //opening a file in writing mode
      out_file = fopen(str, "w");

    // test for files not existing. 
       if (out_file == NULL) 
       {   
           printf("Error! Could not open file\n"); 
           exit(-1); // must include stdlib.h 
       }

       printf("\nEnter the Details of the person:\n\n");
       do
       {
         printf("Enter the User Name:\n");
         scanf("%21s[^\n]",name);

         printf("Enter the Age:\n");
         scanf("%d",&age);


         if(age == 0)
         {
            break;

         }
         else
         {
            // write to file 
            fprintf(out_file,"%s , %d \n", name, age);
         }

       }while(age != 0);

       fclose(out_file);

       read_file = fopen(str,"r");
            //counting the number of lines present in the above file
             sample_chr = getc(read_file);
             while (sample_chr != EOF)
             {
                if (sample_chr == '\n')
                   count_age = count_age +1;

               sample_chr = getc(read_file);
             }             
             rewind(read_file);

             //allocating space for array of structure dynamically
             printf("\n Number of group members : %d \n",count_age);
            count_age = count_age - 1;
             REC1  =  (Group*)malloc(count_age*sizeof(Group));

             //storing the values in array of structures
             for(i=0; i<=count_age; i++)
                fscanf(read_file, "%s , %d", REC1[i].user_Name, &REC1[i].user_age);


             fclose(read_file);

             for(i =0; i<=count_age; i++)
             printf("\n Name : %s   Age : %d \n", REC1[i].user_Name, REC1[i].user_age);

             for(i=0, sum_age=0; i<=count_age; i++)
              sum_age = sum_age + REC1[i].user_age;

             avg_age =  (float)sum_age/(count_age);

            printf("\n\nThe average age is %f\n\n\n", avg_age); 



       return 0;

}