Arithmetic numbers: Difference between revisions

=={{header|Ada}}==

<lang Ada>with Ada.Text_IO; use Ada.Text_IO;

with Ada.Integer_Text_IO; use Ada.Integer_Text_IO;

procedure Main is

procedure divisor_count_and_sum

(n : Positive; divisor_count : out Natural; divisor_sum : out Natural)

is

I : Positive := 1;

J : Natural;

begin

divisor_count := 0;

divisor_sum := 0;

loop

J := n / I;

exit when J < I;

if I * J = n then

divisor_sum := divisor_sum + I;

divisor_count := divisor_count + 1;

if I /= J then

divisor_sum := divisor_sum + J;

divisor_count := divisor_count + 1;

end if;

end if;

I := I + 1;

end loop;

end divisor_count_and_sum;

arithmetic_count : Natural := 0;

composite_count : Natural := 0;

div_count : Natural;

div_sum : Natural;

mean : Natural;

n : Positive := 1;

begin

while arithmetic_count <= 1_000_000 loop

divisor_count_and_sum (n, div_count, div_sum);

mean := div_sum / div_count;

if mean * div_count = div_sum then

arithmetic_count := arithmetic_count + 1;

if div_count > 2 then

composite_count := composite_count + 1;

end if;

if arithmetic_count <= 100 then

Put (Item => n, Width => 4);

if arithmetic_count mod 10 = 0 then

New_Line;

end if;

end if;

if arithmetic_count = 1_000 or else arithmetic_count = 10_000

or else arithmetic_count = 100_000

or else arithmetic_count = 1_000_000

then

New_Line;

Put (Item => arithmetic_count, Width => 1);

Put_Line ("th arithmetic number is" & n'Image);

Put_Line

("Number of composite arithmetic numbers <=" & n'Image & ":" &

composite_count'Image);

end if;

end if;

n := n + 1;

end loop;

end Main;</lang>

{{out}}

<pre>

1 3 5 6 7 11 13 14 15 17

19 20 21 22 23 27 29 30 31 33

35 37 38 39 41 42 43 44 45 46

47 49 51 53 54 55 56 57 59 60

61 62 65 66 67 68 69 70 71 73

77 78 79 83 85 86 87 89 91 92

93 94 95 96 97 99 101 102 103 105

107 109 110 111 113 114 115 116 118 119

123 125 126 127 129 131 132 133 134 135

137 138 139 140 141 142 143 145 147 149

1000th arithmetic number is 1361

Number of composite arithmetic numbers <= 1361: 782

10000th arithmetic number is 12953

Number of composite arithmetic numbers <= 12953: 8458

100000th arithmetic number is 125587

Number of composite arithmetic numbers <= 125587: 88219

1000000th arithmetic number is 1228663

Number of composite arithmetic numbers <= 1228663: 905043

</pre>