diff --git a/step5.c b/step5.c
new file mode 100644
index 0000000..1dd7284
--- /dev/null
+++ b/step5.c
@@ -0,0 +1,104 @@
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+
+// 定义一个结构体来存储学生的信息
+typedef struct {
+    char id[7];
+    char class_num[3];
+    char name[20];
+    float math_score;
+    float physics_score;
+    float english_score;
+} Student;
+
+// 比较函数，用于qsort排序
+int compare_students(const void *a, const void *b) {
+    Student *studentA = (Student *)a;
+    Student *studentB = (Student *)b;
+    int class_cmp = strcmp(studentA->class_num, studentB->class_num);
+    if (class_cmp == 0) {
+        float total_A = studentA->math_score + studentA->physics_score + studentA->english_score;
+        float total_B = studentB->math_score + studentB->physics_score + studentB->english_score;
+        if (total_B - total_A > 0) return -1;
+        else if (total_B - total_A < 0) return 1;
+        else return 0;
+    } else {
+        return class_cmp;
+    }
+}
+
+// 查找学生函数
+Student* find_student(Student students[], int count, const char *key) {
+    for (int i = 0; i < count; i++) {
+        if (strcmp(students[i].id, key) == 0 || strcmp(students[i].name, key) == 0) {
+            return &students[i];
+        }
+    }
+    return NULL;
+}
+
+// 删除学生函数
+void delete_student(Student students[], int *count, Student *to_delete) {
+    for (int i = 0; i < *count; i++) {
+        if (students[i].id == to_delete->id) {
+            for (int j = i; j < *count - 1; j++) {
+                students[j] = students[j + 1];
+            }
+            (*count)--;
+            break;
+        }
+    }
+}
+
+// 打印学生函数
+void print_students(Student students[], int count) {
+    for (int i = 0; i < count; i++) {
+        printf("%s %s %s %.1f %.1f %.1f\n", students[i].id, students[i].class_num, students[i].name,
+               students[i].math_score, students[i].physics_score, students[i].english_score);
+    }
+}
+
+int main() {
+    // 初始化学生信息数组（已排序）
+    Student students[3] = {
+        {"10001", "11", "Zhang", 99.5, 88.5, 89.5},
+        {"10002", "12", "Yang", 77.9, 56.5, 87.5},
+        {"10003", "11", "Liang", 92.5, 99.0, 60.5}
+    };
+    int student_count = 3;
+
+    // 确保学生数组是按要求排序的
+    qsort(students, student_count, sizeof(Student), compare_students);
+
+    // 用户输入待删除学生的学号或姓名
+    char input[50];
+    printf("请输入要删除学生的学号或姓名：");
+    scanf("%s", input);
+    // 清除输入缓冲区中的换行符
+    while (getchar() != '\n');
+
+    // 查找学生信息
+    Student *found_student = find_student(students, student_count, input);
+    if (found_student) {
+        printf("找到学生信息，准备删除...\n");
+        char confirmation[10];
+        printf("Are you sure? (yes/no): ");
+        scanf("%s", confirmation);
+        // 清除输入缓冲区中的换行符
+        while (getchar() != '\n');
+        if (strcmp(confirmation, "yes") == 0 || strcmp(confirmation, "y") == 0) {
+            delete_student(students, &student_count, found_student);
+            printf("学生信息已删除。\n");
+        } else {
+            printf("已取消删除操作。\n");
+        }
+    } else {
+        printf("未找到该学生信息。\n");
+    }
+
+    // 显示剩余学生信息
+    print_students(students, student_count);
+
+    return 0;
+}