帮我写一段C语言的学生成绩管理系统

好的，以下是一个简单的C语言学生成绩管理系统的代码：

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

#define MAX_STUDENTS 100

typedef struct {
    int id;
    char name[20];
    float score;
} Student;

int main() {
    Student students[MAX_STUDENTS];
    int count = 0;

    while (1) {
        printf("Welcome to the student score management system!\n");
        printf("1. Add a student\n");
        printf("2. Show all students\n");
        printf("3. Search a student\n");
        printf("4. Modify a student\n");
        printf("5. Delete a student\n");
        printf("6. Exit\n");
        printf("Please enter your choice (1-6): ");

        int choice;
        scanf("%d", &choice);

        switch (choice) {
            case 1: // Add a student
                if (count >= MAX_STUDENTS) {
                    printf("The system can only store up to %d students.\n", MAX_STUDENTS);
                    break;
                }

                printf("Please enter the student's ID: ");
                scanf("%d", &students[count].id);

                printf("Please enter the student's name: ");
                scanf("%s", students[count].name);

                printf("Please enter the student's score: ");
                scanf("%f", &students[count].score);

                count++;
                break;

            case 2: // Show all students
                if (count == 0) {
                    printf("There are no students in the system.\n");
                    break;
                }

                printf("ID\tName\tScore\n");

                for (int i = 0; i < count; i++) {
                    printf("%d\t%s\t%.2f\n", students[i].id, students[i].name, students[i].score);
                }

                break;

            case 3: // Search a student
                if (count == 0) {
                    printf("There are no students in the system.\n");
                    break;
                }

                printf("Please enter the student's ID: ");

                int search_id;
                scanf("%d", &search_id);

                for (int i = 0; i < count; i++) {
                    if (students[i].id == search_id) {
                        printf("ID\tName\tScore\n");
                        printf("%d\t%s\t%.2f\n", students[i].id, students[i].name, students[i].score);
                        break;
                    }

                    if (i == count - 1) {
                        printf("The student with ID %d is not found.\n", search_id);
                    }
                }

                break;

            case 4: // Modify a student
                if (count == 0) {
                    printf("There are no students in the system.\n");
                    break;
                }

                printf("Please enter the student's ID: ");

                int modify_id;
                scanf("%d", &modify_id);

                for (int i = 0; i < count; i++) {
                    if (students[i].id == modify_id) {
                        printf("Please enter the new score: ");
                        scanf("%f", &students[i].score);
                        printf("The score is modified successfully.\n");
                        break;
                    }

                    if (i == count - 1) {
                        printf("The student with ID %d is not found.\n", modify_id);
                    }
                }

                break;

            case 5: // Delete a student
                if (count == 0) {
                    printf("There are no students in the system.\n");
                    break;
                }

                printf("Please enter the student's ID: ");

                int delete_id;
                scanf("%d", &delete_id);

                for (int i = 0; i < count; i++) {
                    if (students[i].id == delete_id) {
                        for (int j = i; j < count - 1; j++) {
                            students[j] = students[j + 1];
                        }

                        count--;
                        printf("The student is deleted successfully.\n");
                        break;
                    }

                    if (i == count - 1) {
                        printf("The student with ID %d is not found.\n", delete_id);
                    }
                }

                break;

            case 6: // Exit
                printf("Thank you for using the student score management system!\n");
                exit(0);

            default:
                printf("Invalid choice.\n");
                break;
        }

        printf("\n");
    }

    return 0;
}

该程序使用了结构体存储学生信息，并提供了添加、显示、搜索、修改和删除学生信息的功能。