/* ECP: FILEname=fig7_2.c */
/* 1*/   #include <stdio.h>

/* 2*/   #define CompExch( X, Y ) \
/* 3*/       if( X > Y ){ int _Tmp; _Tmp = X; X = Y; Y = _Tmp; }

/* 4*/   /* Print Four Integers, But Avoid Duplicates */

/* 5*/   main( void )
/* 6*/   {
/* 7*/       int Num1, Num2, Num3, Num4;

/* 8*/       printf( "Enter four integers: " );
/* 9*/       if( scanf( "%d %d %d %d",
/*10*/                   &Num1, &Num2, &Num3, &Num4 ) != 4 )
/*11*/       {
/*12*/           printf( "Expected four integers -- exiting...\n" );
/*13*/           return 1;
/*14*/       }

/*15*/       CompExch( Num1, Num2 );
/*16*/       CompExch( Num3, Num4 );
/*17*/       CompExch( Num1, Num3 );
/*18*/       CompExch( Num2, Num4 );
/*19*/       CompExch( Num2, Num3 );

/*20*/       printf( "%d", Num1 );
/*21*/       if( Num2 != Num1 )
/*22*/           printf( " %d", Num2 );
/*23*/       if( Num3 != Num2 )
/*24*/           printf( " %d", Num3 );
/*25*/       if( Num4 != Num3 )
/*26*/           printf( " %d", Num4 );
/*27*/       printf( "\n" );

/*28*/       return 0;	/* Normal Exit */
/*29*/   }