int Menu(void)
{
		int itemSelected;
		printf("Management for Students' scores\n");
		printf("1.Input record\n");
		printf("2.Calculate total and average score of every course\n");
		printf("0.Exit\n");
		printf("Please Input your choice:");
		scanf("%d", &itemSelected); 	// 读入用户输入 
		return itemSelected;
}