C#关系运算符

using System;

class Program {

   static voID Main(string[] args) {
      int a = 21;
      int b = 10;

      if (a == b) {
         Console.Writeline("line 1 - a is equal to b");
      } else {
         Console.Writeline("line 1 - a is not equal to b");
      }

      if (a < b) {
         Console.Writeline("line 2 - a is less than b");
      } else {
         Console.Writeline("line 2 - a is not less than b");
      }

      if (a > b) {
         Console.Writeline("line 3 - a is greater than b");
      } else {
         Console.Writeline("line 3 - a is not greater than b");
      }

      /* Lets change value of a and b */
      a = 5;
      b = 20;

      if (a <= b) { 
         Console.Writeline("line 4 - a is either less than or equal to  b");
      }

      if (b >= a) {
         Console.Writeline("line 5-b is either greater than or equal to b");
      }
   }
}