diff --git a/Task6.c b/Task6.c
new file mode 100644
index 0000000..40a378c
--- /dev/null
+++ b/Task6.c
@@ -0,0 +1,96 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+struct Student{
+		char stunumber[5];
+		int class;
+		char name[10];
+		float grade1;
+		float grade2;
+		float grade3;
+		float sum;
+		}students[3]={{"10001",11,"Zhang",99.5,88.5,89.5,99.5+88.5+99.5},
+			{"10002",12,"Yang",77.9,56.5,87.5,77.9+56.5+87.5},
+			{"10003",11,"Liang",92.5,99.0,60.5,92.5+99.0+60.5}};
+void selection_sort(struct Student arr[], int n) {
+    int i, j, min_idx;
+    
+    //一一检索每个结构体中class的值 
+    for (i = 0; i < n-1; i++) {
+        // 找到最小值的位置 
+        min_idx = i;
+        for (j = i+1; j < n; j++)
+        {
+		
+            if (arr[j].class < arr[min_idx].class)
+            {
+                min_idx = j;
+       		}
+       		else if(arr[j].class == arr[min_idx].class)
+       		{
+       			if(arr[j].sum == arr[min_idx].sum)
+       			{
+       				min_idx=j;
+				}
+			}
+		}
+        // 通过交换位置实现排序
+        struct Student temp = arr[min_idx];
+        arr[min_idx] = arr[i];
+        arr[i] = temp;
+    }
+}
+int main(){
+	int n=3;
+	void selection_sort(struct Student arr[], int n); 
+	selection_sort(students,3);//排序 
+	
+	int idx=-1;//查找待修改学生 
+	char num_or_name[10];
+	printf("请输入您要修改的学生学号或姓名\n");
+	scanf("%s",&num_or_name);
+	for(int i=0;i<3;i++)//检索学生 
+	{
+		if(strcmp(num_or_name, students[i].stunumber) == 0 || strcmp(num_or_name, students[i].name) == 0){
+			idx=i;
+			break;
+		}
+	}
+	
+	if(idx==-1)//学生不存在 
+	{
+		printf("未查找到该学生!\n不予修改!\n");
+		for(int i=0;i < 3;i++)
+		{
+			printf("%s %d %s %.1f %.1f %.1f \n", students[i].stunumber, students[i].class, students[i].name, students[i].grade1, students[i].grade2, students[i].grade3);
+		}
+		return 0;
+	}
+	printf("已查找到该学生!\n");
+	printf("请输入修改后的信息\n"); 
+	struct Student temp;//学生存在且输入修改后的信息 
+	scanf("%s %d %s %f %f %f %f",&temp.stunumber,&temp.class,&temp.name,&temp.grade1,&temp.grade2,&temp.grade3,&temp.sum);
+	students[idx]=temp;
+	
+	selection_sort(students,3);//再一次排序 
+	printf("修改后的学生信息如下:\n");
+	int class0=0;
+	for(int i=0;i < 3;i++){
+		printf("\n");
+		if(students[i].class==class0)
+		{
+			printf("   %s %d %s %.1f %.1f %.1f ", students[i].stunumber, students[i].class, students[i].name, students[i].grade1, students[i].grade2, students[i].grade3);
+		}
+		if(class0!=students[i].class){
+			class0=students[i].class;
+			printf("%d ",class0);
+			printf("%s %d %s %.1f %.1f %.1f ", students[i].stunumber, students[i].class, students[i].name, students[i].grade1, students[i].grade2, students[i].grade3);
+		}
+		if(i==idx)
+		{
+			printf("modifiled");
+		}
+	}
+}
+