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声明变量时如果有小数点便不能使用int格式

 {
            int x = 1;
            int sum = 0;//和，初始化为0
            while (x <= 30)//循环条件
            {
                if (x%2!=0)//筛选条件
                    sum += x;
                    x++;
               
            }
            Console.Write("1-30奇数的和："+sum);
        }

{
            int x;//循环计数变量
            x=1;//行① 请填写计数变量的初始化语句
           
           
            while ( x++<6 )//行② 请填写循环条件
            {
                Console.Write("加油！");
               //行③ 请填写计数变量的自加语句
               
            }
        }

            int y = 87;
            while (y>=1)//请输入
            {
                Console.Write(y+" ");
                y-- ;//请输入
            }

 {
            int year = 8;//年份
            string text;
           text=year%4==0?"闰年":"平年"; //请填写代码
            Console.WriteLine("今年是{0}",text);
        }
       

      double money =60000.00;//存款金额
             if(money>=100000) //请在这里补充多重条件判断
             {
                 Console.WriteLine("送一台微波炉");
            }
            else if(money>=10000)
            {
                 Console.WriteLine("送一袋大米");
            }
            else if(money>=50000)
            {
                 Console.WriteLine("送一套茶具");
            }
           
            else
            {
                 Console.WriteLine("没有礼品");
          
            }

    {
            int x = 5;
            int y = 6;
            if (x >= y)
            {    if (x >= 5)
                Console.WriteLine("5");
            }
            else
            
             if (y >= 6)
                    Console.WriteLine("6");
                else
                    Console.WriteLine("7");
        }
    }
}

程序入口 Main方法   static void Main(string[] args)

输出 Console.Write

   int score = 94;//分数
           if   (score > 95) //判断
            {//分支1
                Console.WriteLine("奖励一辆自行车");
            }
            {//？
                Console.WriteLine("体罚跑步");
            }
            {//？
                Console.WriteLine("体罚8次跑步");

?

 double x = 13.9, y = 24.4;
            double sum = x + y;
            double avg=sum/2;
            Console.WriteLine(avg);

double x, y;
            x = y = 2;//从右向左赋值，x、y的值都是2
            x /= 0.5;
            y -= 2;
            Console.WriteLine(x-y);

只有当&&两边的表达式均为 true 时，整个表达式才为 true 

只要||两边的表达式有一个为 true ，整个表达式即为 true 

  Console.WriteLine(true||false);//输出True
            Console.WriteLine(true&&false);//输出False
            Console.WriteLine(!false);//输出True

 double x = 3.5;
            double y = 3;
            Console.WriteLine(x>y);