diff --git a/xjxt8.cpp b/xjxt8.cpp
new file mode 100644
index 0000000..e154ec8
--- /dev/null
+++ b/xjxt8.cpp
@@ -0,0 +1,176 @@
+#include <stdio.h>
+#include <string.h>
+#define MAX_STUDENTS 100
+typedef struct 
+{
+    char id[20];
+    char mclass[20];
+    char name[20];
+    float score1, score2, score3;
+} Student;
+int numStudents=0;  // 记录当前学生的数量
+Student students[MAX_STUDENTS];
+void showMenu()
+{
+		printf("%30s1.input\n", " ");
+    	printf("%30s2.delete\n", " ");
+    	printf("%30s3.select\n", " ");
+    	printf("%30s4.order\n", " ");
+        printf("%30s5.output\n", " ");
+        printf("%30s6.quit\n", " ");
+        printf("%30splease input your option\n", " ");
+
+}
+void insertStudent() 
+{
+    
+    printf("ID ");
+    scanf("%s", students[numStudents].id);
+    printf("class: ");
+    scanf("%s", &(students[numStudents].mclass));
+    printf("name: ");
+    scanf("%s", students[numStudents].name);
+    printf("score1: ");
+    scanf("%f", &(students[numStudents].score1));
+    printf("score2: ");
+    scanf("%f", &(students[numStudents].score2));
+    printf("score3: ");
+    scanf("%f", &(students[numStudents].score3));
+    numStudents++;
+}
+
+void deleteStudent() 
+{
+    char idOrName[20];
+    scanf("%s", idOrName);
+    int i, j;
+    int found = 0;
+    for (i = 0; i < numStudents; i++) 
+	{
+        if (strcmp(students[i].id, idOrName) == 0 || strcmp(students[i].name, idOrName) == 0) 
+		{
+			found = 1;
+            for (j = i; j < numStudents - 1; j++) 
+			{
+                students[j] = students[j + 1];
+            }
+            numStudents--;
+            break;
+        }
+    }
+    for ( i = 0; i < numStudents; i++)
+    {
+        printf("%s %s %s %.1f %.1f %.1f\n", students[i].id, students[i].mclass, students[i].name, students[i].score1, students[i].score2, students[i].score3);
+    }
+}
+void selectStudent()
+{
+	char idOrName[20];
+	scanf("%s", idOrName);
+	int i,j;
+	int f=0;
+    for (i = 0; i < numStudents; i++) 
+	{
+        if (strcmp(students[i].id, idOrName) == 0 || strcmp(students[i].name, idOrName) == 0) 
+		{
+			f=1;
+            printf("%s %s %s %.1f %.1f %.1f\n", students[i].id, students[i].mclass, students[i].name, students[i].score1, students[i].score2, students[i].score3);
+        }
+	}
+	if(f==0) printf("there is no eligible student\n");
+}
+
+void orderStudent()
+{
+	int i,j;
+    for (i = 0; i < numStudents; i++) 
+	{          
+        for (j=i+1;j<numStudents;j++) 
+		{  
+             if (students[i].mclass > students[j].mclass || (students[i].mclass == students[j].mclass && students[i].score1 + students[i].score2 + students[i].score3 < students[j].score1 + students[j].score2 + students[j].score3)) 
+			{
+                    Student temp = students[j];
+                    students[j] = students[i];
+                    students[i] = temp;
+            }
+        }
+    }
+    for ( i = 0; i < numStudents; i++)
+    {
+        printf("%s %s %s %.1f %.1f %.1f\n", students[i].id, students[i].mclass, students[i].name, students[i].score1, students[i].score2, students[i].score3);
+    }
+}
+void printStudent() 
+{
+	int i=0;
+    for (i = 0; i < numStudents; i++) 
+	{
+        printf("%s %s %s %.1f %.1f %.1f\n", students[i].id, students[i].mclass, students[i].name, students[i].score1, students[i].score2, students[i].score3);
+    }
+}
+
+int main() 
+{
+	int choice;
+    char a[4];
+    while (1) 
+	{
+		showMenu();
+        scanf("%d", &choice);
+        switch (choice) 
+		{
+            case 1:
+                insertStudent();
+                while(1)
+                {
+                	printf("continue?\n");
+                	scanf("%s",&a);
+                	if(strcmp(a,"yes")==0)
+                	{
+                		insertStudent();
+                		continue;
+					}
+					else break;
+				}
+                break;
+            case 2:
+                deleteStudent();
+                while(1)
+                {
+                	printf("continue?\n");
+                	scanf("%s",&a);
+                	if(strcmp(a,"yes")==0)
+                	{
+                		deleteStudent();
+                		continue;
+					}
+					else break;
+				}
+                break;
+            case 3:
+                selectStudent();
+                while(1)
+                {
+                	printf("continue?\n");
+                	scanf("%s",&a);
+                	if(strcmp(a,"yes")==0)
+                	{	
+                		selectStudent();
+                		continue;
+					}
+					else break;
+				}
+                break;
+            case 4:
+                orderStudent();
+                break;
+            case 5:
+            	printStudent();
+            	break;
+            case 6:
+                return 0;
+        }
+        //showMenu();
+    }
+}
+