我在程序中得到一些未报告的值

Question

My program is to ask the user to enter the name and age of the person in his group. The number of person is not known to the user in the beginning of the program. The user keeps on entering the data till the user enters the age zero . The program finally prints the average age.

The source code is below

#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;

}

while i am compiling it doesn't shows any error. When i am running it shows exe file stopped working.

Answer 1

the following is working

there had to be changed the format in scanf() of name[] ( http://www.cplusplus.com/reference/cstdio/scanf/ )

, the fclose(out_file) had to be moved and the ending condition of the while loop had to be changed ...

#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;

}