大作业，，，

students = [
{"id": 1, "scores": [85, 90, 88]},
{"id": 2, "scores": [79, 82, 91]},
{"id": 3, "scores": [95, 89, 92]}
]

def get_student(target_id):
    for student in students:
        if student["id"] == target_id:
            return student
    return None
def show_students():
    print("所有学生成绩：")
    for student in students:
        print("id:", student["id"], " 成绩:", student["scores"])
def add_student():
    print("请输入新学生id（整数）：")
    new_id = int(input())
    if get_student(new_id) is not None:
        print("id已存在，添加失败")
        return
    print("请输入成绩数量（整数，至少1）：")
    score_count = int(input())
    if score_count < 1:
        print("成绩数量至少为1，添加失败")
        return
    scores = []
    for i in range(score_count):
        print(f"请输入第{i+1}个成绩：")
        score = int(input())
        scores.append(score)
    students.append({"id": new_id, "scores": scores})
    print("添加成功")
def modify_student():
    print("请输入要修改的学生id（整数）：")
    target_id = int(input())
    student = get_student(target_id)
    if student is None:
        print("未找到该学生，修改失败")
        return
    print("请输入新的成绩数量（整数）：")
    new_count = int(input())
    new_scores = []
    for i in range(new_count):
        print(f"请输入第{i+1}个新成绩：")
        score = int(input())
        new_scores.append(score)
    student["scores"] = new_scores
    print("修改成功")
def delete_student():
    print("请输入要删除的学生id（整数）：")
    target_id = int(input())
    student = get_student(target_id)
    if student is None:
        print("未找到该学生，删除失败")
        return
    students.remove(student)
    print("删除成功")
def analyze_scores():
    total_students = len(students)
    print("成绩统计分析：")
    print("1. 班级总人数：", total_students)    
    if total_students == 0:
        return    
    total_scores = []
    for student in students:
        total = sum(student["scores"])
        total_scores.append(total)
    avg_total = sum(total_scores) / total_students
    print("2. 平均总分：", round(avg_total, 1))
    max_total = max(total_scores)
    print(f"3. 最高分学生（总分{max_total}）：")
    for i in range(total_students):
        if total_scores[i] == max_total:
            print("   id=", students[i]["id"], "，总分=", total_scores[i], sep="")
    id_total = [(students[i]["id"], total_scores[i]) for i in range(total_students)]
    sorted_id_total = sorted(id_total, key=lambda x: x[1], reverse=True)   
    print("4. 按总分排名：")
    for rank, (sid, total) in enumerate(sorted_id_total, 1):
        print(f"   排名{rank}：id={sid}，总分={total}")
def main():
    while True:
        print("\n班级成绩管理系统")
        print("1. 查看所有学生成绩")
        print("2. 添加新学生")
        print("3. 修改学生成绩")
        print("4. 删除学生")
        print("5. 成绩统计分析")
        print("6. 退出系统")
        print("请输入功能编号（1-6）：")
        try:
            choice = int(input())

            if choice == 1:
                show_students()
            elif choice == 2:
                add_student()
            elif choice == 3:
                modify_student()
            elif choice == 4:
                delete_student()
            elif choice == 5:
                analyze_scores()
            elif choice == 6:
                print("系统退出，再见！")
                break
            else:
                print("请输入1-6之间的整数")
        except ValueError:
            print("输入错误，请输入一个整数")
if __name__ == "__main__":
    main()