/* ECP: FILEname=fig7_3.c */
/* 1*/   #include <stdio.h>

/* 2*/   /* Print Four Integers, But Avoid Duplicates */

/* 3*/   #define CompExch( X, Y ) \
/* 4*/       if( X > Y ) { int _Tmp; _Tmp = X; X = Y; Y = _Tmp; }

/* 5*/   main( void )
/* 6*/   {
/* 7*/       int Num[ 4 ];   /* Num[ 0 ] Num[ 1 ] Num[ 2 ] Num[ 3 ] */

/* 8*/       printf( "Enter four integers: " );
/* 9*/       if( scanf( "%d %d %d %d",
/*10*/               &Num[ 0 ], &Num[ 1 ], &Num[ 2 ], &Num[ 3 ] ) != 4 )
/*11*/       {
/*12*/           printf( "Expected four integers -- exiting...\n" );
/*13*/           return 1;
/*14*/       }

/*15*/       CompExch( Num[ 0 ], Num[ 1 ] );
/*16*/       CompExch( Num[ 2 ], Num[ 3 ] );
/*17*/       CompExch( Num[ 0 ], Num[ 2 ] );
/*18*/       CompExch( Num[ 1 ], Num[ 3 ] );
/*19*/       CompExch( Num[ 1 ], Num[ 2 ] );

/*20*/       printf( "%d", Num[ 0 ] );
/*21*/       if( Num[ 1 ] != Num[ 0 ] )
/*22*/           printf( " %d", Num[ 1 ] );
/*23*/       if( Num[ 2 ] != Num[ 1 ] )
/*24*/           printf( " %d", Num[ 2 ] );
/*25*/       if( Num[ 3 ] != Num[ 2 ] )
/*26*/           printf( " %d", Num[ 3 ] );
/*27*/       printf( "\n" );

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