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PROGRAM sort_array;
 
{ SORT.PAS: Demonstrates sorting array of pointers. }
 
CONST
    size = 4;
 
TYPE
    real_p       = ^Real;
    real_array_t = ARRAY[1..size] OF Real;
    real_ptrs_t  = ARRAY[1..size] OF real_p;
 
CONST
    r : real_array_t = (3.333, 1.111, 2.222, 4.444);
 
VAR
    i     : Integer;
    r_ptr : real_ptrs_t;
 
PROCEDURE show( ptr_array : real_ptrs_t;
                r_array   : real_array_t );
 
VAR
    j : Integer;
 
BEGIN
    Write( '-----------------------------' );
    Writeln( '-----------------------------' );
    FOR j := 1 TO size DO
    BEGIN
        Write( 'r_ptr[', j, ']^ = ', ptr_array[j]^:4:3 );
        Write( '    r_ptr[', j, '] = ', LongInt(ptr_array[j]) );
        Writeln( '    r[', j, '] = ', r_array[j]:4:3 );
    END;
END; { procedure show }
 
PROCEDURE sort( VAR ptr_array : real_ptrs_t );
 
VAR
    x, x1 : Integer;
    temp  : real_p;
 
BEGIN
    FOR x := 1 TO size DO
        FOR x1 := (x + 1) TO (size - 1) DO
            IF ptr_array[x]^ > ptr_array[x1]^ THEN
            BEGIN
                temp := ptr_array[x1];
                ptr_array[x1] := ptr_array[x];
                ptr_array[x] := temp;
            END; { IF clause and FOR statements }
END; { procedure sort }
 
BEGIN
 
    { Set up array of pointers. }
    FOR i := 1 TO size DO
        r_ptr[i] := @r[i];
 
    show( r_ptr, r );
    sort( r_ptr );
    show( r_ptr, r );
 
END.