我已经编写了一个基于结构数组的程序，它的所有部分都很好，但我的一个函数 sort_student 函数有一个错误。在此代码中，首先用户将输入一些学生，他们的信息包括名字、姓氏、ID 和平均值，之后用户将有几个选项，除了排序功能之外，所有选项都可以。这个函数的主要问题是它只能对平均值进行排序，然后它将第一个学生的名字和姓氏以及 ID 放入所有学生的结构中。我不知道如何解决它。 我想我不得不说，我在编码方面是业余爱好者，所以如果你想帮忙，请帮忙，如果你不想，请不要发表负面评论。谢谢。
这是有问题的功能：
void sort_student()
{
float selected_item;
int j;
for (int i = 0; i < students_count; i++)
{
selected_item = student[i].average;
j = i - 1;
while ((j >= 0) && (selected_item < student[j].average))
{
student[j + 1].average = student[j].average;
strcpy(student[j + 1].first_name, student[j].first_name);
strcpy(student[j + 1].last_name, student[j].last_name);
strcpy(student[j + 1].id, student[j].id);
j--;
}
student[j + 1].average = selected_item;
}
printf("The students are sorted now.");
}
如果您需要，这是我的全部代码：
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
struct school
{
char first_name[80];
char last_name[80];
char id[12];
float average;
};
struct school *student;
int students_count;
int con = 1;
int chosen_option;
FILE *fptr;
void options();
void add_student();
void remove_student();
void search_student();
void sort_student();
void save_to_file();
void upload_students();
int main() {
student = calloc(300, sizeof *student);
printf("How many students do you have ? (MAX = 300)\n");
scanf("%d", &students_count);
for (int i = 0; i < students_count; i++)
{
printf("Whats your student number %d first name ? \n", i+1);
scanf("%79s", student[i].first_name);
printf("Whats your student number %d last name ? \n", i+1);
scanf("%79s", student[i].last_name);
printf("Whats your student number %d id ? \n", i+1);
scanf("%11s", student[i].id);
printf("Whats your student number %d average ? \n", i+1);
scanf("%f", &student[i].average);
}
printf("\nOK! you've entered the students and their information successfully.\n");
while (con == 1)
{
options();
}
return 0;
}
void options()
{
printf("\nOK! Do you want to continue? (Yes : 1/N : 0)");
scanf("%d", &con);
if (con == 1)
{
printf("What do you want to do now ? \n");
printf("\n1. Add student\n");
printf("\n2. Remove student\n");
printf("\n3. Search student\n");
printf("\n4. Sort by average\n");
printf("\n5. save the students information in a file\n");
printf("\n6. upload all of students information\n");
printf("\nPlease enter the number of you choice : ");
scanf("%d", &chosen_option);
switch (chosen_option) {
case 1:
add_student();
break;
case 2:
remove_student();
break;
case 3:
search_student();
break;
case 4:
sort_student();
break;
case 5:
save_to_file();
break;
case 6:
upload_students();
break;
default:
printf("Your chosen option is invalid\n");
break;
}
}
else if (con == 0)
{
printf("OK! You don't want to continue. Bye!\n");
exit(0);
} else
{
printf("You can't continue with invalid options.\n");
exit(0);
}
}
void add_student()
{
printf("Whats your (new) student number %d first name ? \n", students_count+1);
scanf("%79s", student[students_count].first_name);
printf("Whats your (new) student number %d last name ? \n", students_count+1);
scanf("%79s", student[students_count].last_name);
printf("Whats your (new) student number %d id ? \n", students_count+1);
scanf("%11s", student[students_count].id);
printf("Whats your (new) student number %d average ? \n", students_count+1);
scanf("%f", &student[students_count].average);
students_count ++;
printf("OK! You've entered the new student information successfully.\n");
}
void remove_student()
{
char removing_id[12];
int i;
printf("\nPlease enter the id of student that you want to remove : ");
scanf("%11s", removing_id);
for (i = 0; i < students_count; i++)
{
if (strcmp(removing_id, student[i].id) == 0)
{
for (int j = i; j < students_count - 1; j++)
{
strcpy(student[j].first_name, student[j+1].first_name);
strcpy(student[j].last_name, student[j+1].last_name);
strcpy(student[j].id, student[j+1].id);
student[j].average = student[j+1].average;
}
break;
}
}
if(i == students_count)
{
printf("The id is not available!");
exit(0);
}
else
{
students_count--;
printf("The student removed successfully.");
}
}
void search_student()
{
char searching_id[12];
int i;
printf("\nPlease enter the id of student that you want to search : ");
scanf("%11s",searching_id);
for (i = 0; i < students_count; i++)
{
if (strcmp(searching_id, student[i].id) == 0)
{
printf("\nFIRSTNAME LASTNAME ID AVERAGE\n");
printf("\n%s\t%s\t%s\t%.2f\n", student[i].first_name, student[i].last_name, student[i].id,
student[i].average);
}
}
if (i == students_count)
{
printf("We don't have student with this id.");
}
}
void sort_student()
{
float selected_item;
int j;
for (int i = 0; i < students_count; i++)
{
selected_item = student[i].average;
j = i - 1;
while ((j >= 0) && (selected_item < student[j].average))
{
student[j + 1].average = student[j].average;
strcpy(student[j + 1].first_name, student[j].first_name);
strcpy(student[j + 1].last_name, student[j].last_name);
strcpy(student[j + 1].id, student[j].id);
j--;
}
student[j + 1].average = selected_item;
}
printf("The students are sorted now.");
}
void save_to_file()
{
fptr = fopen("MY SCHOOL FILE.txt", "w");
fprintf(fptr, "# FIRSTNAME LASTNAME ID AVERAGE\n");
for(int i = 0; i < students_count; i++)
{
fprintf(fptr, "%d\t%s\t%s\t%s\t%.2f\n", i+1, student[i].first_name, student[i].last_name,
student[i].id, student[i].average);
}
fclose(fptr);
printf("\nThe file is in project folder.\n");
}
void upload_students()
{
printf("# FIRSTNAME LASTNAME ID AVERAGE\n");
for (int i = 0; i < students_count; i++)
{
printf("%d\t%s\t%s\t%s\t%.2f\n", i+1, student[i].first_name, student[i]. last_name,
student[i].id, student[i].average);
}
}
对于初学者来说，函数
sort_student在这个 while 循环中
while ((j >= 0) && (selected_item < student[j].average))
{
student[j + 1].average = student[j].average;
strcpy(student[j + 1].first_name, student[j].first_name);
strcpy(student[j + 1].last_name, student[j].last_name);
strcpy(student[j + 1].id, student[j].id);
j--;
}
元素student[i]的所有数据成员都被覆盖。
该函数可以如下所示
void sort_student( void )
{
for ( int i = 1; i < students_count; i++ )
{
struct school current_student = student[i];
int j = i;
for ( ; j != 0 && current_student.average < student[j - 1].average; --j )
{
student[j] = student[j-1];
}
if ( j != i ) student[j] = current_student;
}
printf("The students are sorted now.");
}