diff --git a/task3.cpp b/task3.cpp
new file mode 100644
index 0000000..5201d87
--- /dev/null
+++ b/task3.cpp
@@ -0,0 +1,106 @@
+#include <stdio.h>
+//定义结构体
+struct Student
+{
+	int ID;//学号 
+	float math_grade;
+	float physics_grade;
+	float English_grade;
+	float sum;
+	float average; 
+};
+void Show_The_Main_interface()
+{
+	//显示主界面 
+	for(int i=1;i<=30;i++)
+	{
+		printf(" ");
+	}
+	printf("1.Input\n");
+	for(int i=1;i<=30;i++)
+	{
+		printf(" ");
+	}
+	printf("2.Output\n");
+	for(int i=1;i<=30;i++)
+	{
+		printf(" ");
+	}
+	printf("3.Order\n");
+	for(int i=1;i<=30;i++)
+	{
+		printf(" ");
+	}
+	printf("4.Quit\n");
+}
+
+void Output_Prompts(char choice)
+{
+	//输出提示信息 
+	if(choice=='i')
+	{
+		printf("Please input info of the three students:\n");
+	}
+	else if(choice=='o')
+	{
+		printf("You are trying to Output info\n");
+	}
+	else if(choice=='m')
+	{
+		printf("You are trying to Make things ordered\n");
+	}
+	else if(choice=='q')
+	{
+		printf("You are about to Quit\n");
+	}
+	else
+	{
+		printf("Wrong input\n");
+	}
+}
+int main()
+{	
+	//显示主界面
+	Show_The_Main_interface();
+	//用户输入 
+	char choice;
+	scanf("%c",&choice);
+	//输出提示信息 
+	Output_Prompts(choice); 
+	
+	//输入学生信息 
+	struct Student information[3];
+	for(int i=0;i<3;i++)
+	{
+		scanf("%d%f%f%f",&information[i].ID,&information[i].math_grade,\
+		&information[i].physics_grade,&information[i].English_grade);
+		information[i].sum=information[i].math_grade+information[i].physics_grade\
+		+information[i].English_grade;
+	 	information[i].average=information[i].sum/3.0;
+	 } 
+	 
+	 //排序 
+	for(int i=0;i<3;i++)
+	{
+		for(int j=0;j<3-i-1;j++)
+		{
+			if(information[j].sum>information[j+1].sum)
+			{
+				//此处我们直接交换结构体 
+				struct Student tmp;
+				tmp=information[j];
+				information[j]=information[j+1];
+				information[j+1]= tmp;
+			}
+		}
+	 } 
+	 
+	 //按要求输出
+	for(int i=0;i<3;i++)
+	{
+		printf("%d,%.1f,%.1f\n",information[i].ID,\
+		information[i].sum,information[i].average);
+	 }  
+}
+
+