static void Main(string[] args)
        {
            //声明整型数组，保存一组整数
            int[] num = new int[]{ 3,34,43,2,11,19,30,55,20};
            bool hasNbei =false;
            foreach (int x in num)
           {
              if(x%7==0)
                {
                    hasNbei=true;
                    break;
                }
           }
            if(hasNbei)
                 Console.WriteLine("有7的整数倍");
            else
                 Console.WriteLine("没有7的整数倍");
           
        }