1

daima

@@ -0,0 +1,90 @@
+}
+    else
+    {
+        printf("学生已存在");
+    }
+}
+
+//修改
+void update_data(void)
+{
+    int num;
+    printf("输入学生学号：");
+    scanf("%d", &num);
+    int f = 0;
+    for (int i = 0; i < num_parts; i++)
+    {
+        if (num == stu[i].number)
+        {
+            f = 1;
+            break;
+        }
+    }
+    if (f == 0)
+    {
+        printf("学生不存在");
+    }
+    else
+    {
+        printf("输入学生学号：");
+        scanf("%d", &stu[num].number);
+        printf("输入学生姓名：");
+        scanf("%s", stu[num].name);
+        printf("输入学生成绩：");
+        scanf("%d", &stu[num].score);
+        printf("学生 %d 已更新", num);
+    }
+}
+
+//删除
+void delete_data(void)
+{
+    int num;
+    printf("输入学生学号：");
+    scanf("%d", &num);
+    int f = 0, i, j;
+    for (i = 0; i < num_parts; i++)
+    {
+        if (num == stu[i].number)
+        {
+            f = 1;
+            break;
+        }
+    }
+    if (f == 0)
+    {
+        printf("学生不存在");
+    }
+    else
+    {
+        for (j = i; j < num_parts - 1; j++)
+        {
+            stu[j] = stu[j + 1];
+        }
+        num_parts--;
+        printf("删除成功");
+    }
+}
+
+void read_data(void)
+{
+    puts("读取数据");
+    printf("请输入文件名");
+    char filename[256];
+    scanf("%s", filename);
+
+    FILE *fp = fopen(filename, "r");
+    if (fp == NULL)
+    {
+        perror(filename);
+        return;
+    }
+    int i = 0;
+    while (fscanf(fp, "%d,%[^,],%d", &stu[i].number, stu[i].name, &stu[i].score) == 3)
+    {
+        i++;
+    }
+    fclose(fp);
+    num_parts = i;
+    printf("读取 %d 记录\n", num_parts);
+}