41 lines
1.4 KiB
Text
41 lines
1.4 KiB
Text
begin
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% returns the minimum of a and b %
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integer procedure min ( integer value a, b ) ; if a < b then a else b;
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% find and print Hamming Numbers %
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% Algol W only supports 32-bit integers so we just find %
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% the 1691 32-bit Hamming Numbers %
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integer MAX_HAMMING;
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MAX_HAMMING := 1691;
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begin
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integer array H( 1 :: MAX_HAMMING );
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integer p2, p3, p5, last2, last3, last5;
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H( 1 ) := 1;
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last2 := last3 := last5 := 1;
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p2 := 2;
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p3 := 3;
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p5 := 5;
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for hPos := 2 until MAX_HAMMING do begin
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integer m;
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% the next Hamming number is the lowest of the next multiple of 2, 3, and 5 %
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m := min( min( p2, p3 ), p5 );
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H( hPos ) := m;
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if m = p2 then begin
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last2 := last2 + 1;
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p2 := 2 * H( last2 )
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end if_used_power_of_2 ;
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if m = p3 then begin
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last3 := last3 + 1;
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p3 := 3 * H( last3 )
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end if_used_power_of_3 ;
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if m = p5 then begin
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last5 := last5 + 1;
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p5 := 5 * H( last5 )
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end if_used_power_of_5 ;
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end for_hPos ;
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i_w := 1;
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s_w := 1;
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write( H( 1 ) );
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for i := 2 until 20 do writeon( H( i ) );
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write( H( MAX_HAMMING ) )
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end
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end.
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