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明解Ｃ言語入門編 > 7. 基本型 >

Delphi



program Project1;
{$APPTYPE CONSOLE}
uses

    SysUtils;
function count_bits(x:Longword):Integer;

var

    count:Integer;

begin

    count := 0;

    while (x <> 0) do

    begin

        if x and 1 <> 0 then inc(count);

        x := x shr 1;

    end;

    result := count;

end;
function int_bits():Integer;

begin

    result := count_bits(Longword(not 0));

end;
procedure print_bits(x:Longword);

var

    i: Integer;

begin

    for i := int_bits() - 1 downto 0 do

    begin

        if x shr i and 1 <> 0 then

            write('1')

        else

            write('0');

    end;
    writeln('');

end;
procedure main();

var

    na: Longword;

begin

    na := 12345;

    write('A       = '); print_bits(na);

    write('A >> 1  = '); print_bits(na shr 1);

    write('A >> 2  = '); print_bits(na shr 2);

    write('A >> 3  = '); print_bits(na shr 3);

    write('A >> 4  = '); print_bits(na shr 4);

    writeln('');
    write('A       = '); print_bits(na);

    write('A << 1  = '); print_bits(na shl 1);

    write('A << 2  = '); print_bits(na shl 2);

    write('A << 3  = '); print_bits(na shl 3);

    write('A << 4  = '); print_bits(na shl 4);

end;
begin

    main;

end.

実行結果



S:\>lesson057\project1.exe

A       = 00000000000000000011000000111001

A >> 1  = 00000000000000000001100000011100

A >> 2  = 00000000000000000000110000001110

A >> 3  = 00000000000000000000011000000111

A >> 4  = 00000000000000000000001100000011
A       = 00000000000000000011000000111001

A << 1  = 00000000000000000110000001110010

A << 2  = 00000000000000001100000011100100

A << 3  = 00000000000000011000000111001000

A << 4  = 00000000000000110000001110010000