C语言关系运算符

#include <stdio.h>

main() {

   int a = 21;
   int b = 10;
   int c ;

   if( a == b ) {
      printf(Line 1 - a is equal to b\n );
   } else {
      printf(Line 1 - a is not equal to b\n );
   }

   if ( a < b ) {
      printf(Line 2 - a is less than b\n );
   } else {
      printf(Line 2 - a is not less than b\n );
   }

   if ( a > b ) {
      printf(Line 3 - a is greater than b\n );
   } else {
      printf(Line 3 - a is not greater than b\n );
   }

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

   if ( a <= b ) {
      printf(Line 4 - a is either less than or equal to  b\n );
   }

   if ( b >= a ) {
      printf(Line 5 - b is either greater than  or equal to b\n );
   }
}