diff --git a/学生成绩管理系统.cpp b/学生成绩管理系统.cpp
new file mode 100644
index 0000000..e07baa4
--- /dev/null
+++ b/学生成绩管理系统.cpp
@@ -0,0 +1,332 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdbool.h>
+#define len sizeof(struct grade)
+struct grade
+{ 
+char id[10];
+char clas[10];
+char name[20];
+float score1;
+float score2;
+float score3;
+float score;
+struct grade *next;
+struct grade *prev;
+};
+void print()
+{
+	int i;
+	for(i=1;i<=30;i++)
+	{
+		printf(" ");
+	}
+};
+void menu(struct grade *head,struct grade *tail)
+{
+	void student1(struct grade *head);
+	void delet(struct grade *head,struct grade *tail);
+	void printgrade(struct grade *head,struct grade *tail);
+	void selecty(struct grade *head,struct grade *tail);
+	void arra(struct grade *head,struct grade *tail);
+	char c;
+	print();
+	printf("1.input\n");
+	print();
+	printf("2.delete\n"); 
+	print();
+	printf("3.select\n");
+	print();
+	printf("4.order\n");
+	print();
+	printf("5.output\n");
+	print();
+	printf("6.quit\n");
+	printf("please input your option\n");
+    scanf("%s",&c);
+	switch(c)
+	{
+	case'1':student1(head);break;
+	case'2':delet(head,tail);break;
+	case'3':selecty(head,tail);break;
+	case'4':arra(head,tail);break;
+	case'5':printgrade(head,tail);break;
+	case'6':break;
+	default:printf("Wrong input");	
+	return;
+	}
+}
+void printgrade1(struct grade *p)
+{
+	printf("%s,",p->id);
+	printf("%s,",p->clas);
+	printf("%s,",p->name);
+	printf("%4.1f,",p->score1);
+	printf("%4.1f,",p->score2);
+	printf("%4.1f,",p->score3);
+	printf("%5.1f",p->score);
+	printf("\n");
+}
+void printgrade(struct grade *head,struct grade *tail)
+{
+		if(head==NULL)
+	{
+		printf("error!\n");
+		menu(head,tail);
+		return;
+	}
+	else
+	{
+	struct grade *p=head;
+	while(p->next!=NULL)
+	{
+		printgrade1(p);
+		p=p->next;
+	}
+	printgrade1(tail);
+	printf("\n");
+	menu(head,tail);
+	return;
+    }
+} 
+void judge(struct grade *head,struct grade *tail,struct grade *next,struct grade *prev,struct grade *pres)
+{
+  bool judgechar(char str1[],char str2[]);
+  void student2(struct grade *head,struct grade *tail,struct grade *next,struct grade *prev,struct grade *pres);
+  char s[3],s1[10]="yes";
+  printf("countinue?\n");
+  scanf("%s",s);
+  if(judgechar(s,s1))
+  {student2(head,tail,next,prev,pres);
+  return;}
+  else
+  {menu(head,tail);
+  return;}
+}
+void fill(struct grade *p)
+{
+  printf("id: ");
+  scanf("%s",(*p).id);
+  printf("class: ");
+  scanf("%s",(*p).clas);
+  printf("name: ");
+  scanf("%s",(*p).name);
+  printf("score1: ");
+  scanf("%f",&(*p).score1);
+  printf("score2: ");
+  scanf("%f",&(*p).score2);
+  printf("score3: ");
+  scanf("%f",&(*p).score3);
+  p->score=p->score1+p->score2+p->score3;
+}
+void student1(struct grade *head)
+{
+  void student2(struct grade *head,struct grade *tail,struct grade *next,struct grade *prev,struct grade *pres);		
+  struct grade *p,*tail;
+  p=(struct grade *)malloc(len);
+  fill(p);
+  p->next=NULL;
+  p->prev=NULL;
+  head=p;
+  tail=p;
+  judge(head,tail,(*p).next,(*p).prev,p);
+  return;
+}
+void student2(struct grade *head,struct grade *tail,struct grade *next,struct grade *prev,struct grade *pres)
+{
+	struct grade *p,*q=pres;
+	p=(struct grade *)malloc(len); 
+	fill(p);
+	q->next=p;
+	p->next=NULL;
+	p->prev=q;
+	tail=p;
+	judge(head,tail,next,prev,p);
+	return;
+}
+bool judgechar(char str1[],char str2[])
+{
+	int Len=strlen(str2),i,m=1;
+	for(i=0;i<=Len-1;i++)
+	{
+		if(str1[i]!=str2[i])
+		{
+			m=0;
+			break;
+		}
+	}
+	if(m==1)
+	return true;
+	else
+	return false;
+}
+void delet(struct grade *head,struct grade *tail)
+{
+	if(head==NULL||head->next==NULL)
+	{
+		printf("error!\n");
+		menu(head,tail);
+		return;
+	}
+	else
+	{
+	char str[256],str1[10],str2[10]="yes";
+	struct grade *p=head->next;
+	printf("The student you want to delete: ");
+	scanf("%s",str);
+	if(judgechar(head->id,str)||judgechar(head->name,str))
+	{
+		struct grade *p1;
+		p1=head->next;
+		free(head);
+		head=p1;
+	}
+	else
+	{
+	if(judgechar(tail->id,str)||judgechar(tail->name,str))
+	{
+		struct grade *p1;
+		(*(tail->prev)).next=NULL;
+		p1=tail->prev;
+		free(tail);
+		tail=p1;
+	}
+	else
+	{
+	while(p->next!=NULL)
+	{
+		if(judgechar(p->id,str)||judgechar(p->name,str))
+		{
+			(*(p->prev)).next=p->next;
+			(*(p->next)).prev=p->prev;
+			free(p);
+			break;
+		}
+		else
+		p=p->next;
+	}
+	}
+	}
+	printf("Do you want to delete anymore?\n");
+	scanf("%s",str1);
+	if(judgechar(str1,str2))
+	{
+		if(head->next==NULL)
+		{
+			printf("error!\n");
+			menu(head,tail);
+			return;
+		}
+		else
+		{
+		delet(head,tail);
+		return;
+		}
+	}
+	else
+	{
+	   printgrade(head,tail);	
+	   return;
+	}
+    }
+}
+void swap1(char str1[],char str2[])
+{
+	char str[100];
+	strcpy(str,str2);
+	strcpy(str2,str1);
+	strcpy(str1,str);
+}
+void swap(struct grade *p,struct grade *q)
+{
+	int temp;
+	swap1(p->id,q->id);
+	swap1(p->name,q->name);
+	swap1(p->clas,q->clas);
+	temp=q->score1;
+	q->score1=p->score1;
+	p->score1=temp;
+	temp=q->score2;
+	q->score2=p->score2;
+	p->score2=temp;
+	temp=q->score3;
+	q->score3=p->score3;
+	p->score3=temp;
+	temp=q->score;
+	q->score=p->score;
+	p->score=temp;
+}
+void arra(struct grade *head,struct grade *tail)
+{
+	struct grade *p,*q;
+	if(head==NULL)
+	{
+		printf("error!\n");
+		menu(head,tail);
+		return;
+	}
+	else
+	{
+	for(p=head;p->next!=NULL;p=p->next)
+	{
+		if(p->next==tail)
+		{
+			if(tail->score>p->score)
+			swap(p,tail);
+		}
+		else
+		{
+			for(q=p->next;q->next!=NULL;q=q->next)
+			{
+				if(q->score>p->score)
+				swap(p,q);
+			}
+			if(tail->score>p->score)
+			swap(p,tail);
+		}
+	}
+	printgrade(head,tail);
+	return;
+    }
+}
+void selecty(struct grade *head,struct grade *tail)
+{
+	struct grade *p;
+	char str[100];
+	int m=0;
+		if(head==NULL)
+	{
+		printf("error!\n");
+		menu(head,tail);
+		return;
+	}
+	else
+	{
+	printf("Who do you want to inquire: ");
+	scanf("%s",str);
+	for(p=head;p->next!=NULL;p=p->next)
+	{
+		if(judgechar(p->id,str)||judgechar(p->name,str))
+		{
+			printgrade1(p);
+			m++;
+			menu(head,tail);
+		}
+	}
+	if(judgechar(tail->id,str)||judgechar(tail->name,str))
+	{
+		printgrade1(tail);
+		m++;
+		menu(head,tail);
+	}
+	if(m==0)
+	printf("there is no eligible student\n");
+	return;
+}
+}
+int main()
+{	struct grade *head=NULL,*tail;
+	menu(head,tail);
+	return 0;
+}