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Happy numbers: Difference between revisions

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Happy numbers (view source)

Revision as of 14:23, 17 September 2022

769 bytes removed ,  1 year ago
→‎{{header|ALGOL W}}: Slightly simpler version
(→‎{{header|ALGOL W}}: Removed near duplicate entry)
Tag: Manual revert
(→‎{{header|ALGOL W}}: Slightly simpler version)
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=={{header|ALGOL W}}==
<syntaxhighlight lang="algolw">begin
begin % find some happy numbers: numbers whose digit-square sums become 1 %
% printwhen repeatedly applied the first 8 happy numbers %▼
% returns true if n is happy, false otherwise; n must be >= 0 %
logical procedure isHappy ( integer value n ) ;
if n < 2 then true▼
else begin▼
% seen is used to hold the values of the cycle of the %
% digit square sums, as noted in the Batch File %▼
% version, we do not need a large array. The digit %
% square sum of 9 999 999 999 is 810... %
integer array seen( 0 :: 32 );▼
integer number, trys;▼
number := n;▼
trys := -1;▼
while begin▼
logical terminated;▼
integer tPos;▼
terminated := false;▼
tPos := 0;▼
while not terminated and tPos <= trys do begin▼
terminated := seen( tPos ) = number;▼
tPos := tPos + 1▼
end while_not_terminated_and_tPos_lt_trys ;
number > 1 and not terminated
end do begin▼
integer sum;▼
trys := trys + 1;
seen( trys ) := number;
sum := 0;
while number > 0 do begin
integer digit;
digit := number rem 10;
number := number div 10;
sum := sum + ( digit * digit )
end while_number_gt_0 ;
number := sum
end while_number_gt_1_and_not_terminated ;
number = 1▼
end isHappy ;▼
▲ % print the first 8 happy numbers %
begin
▲ % the %largest digit -square sums,sun asfor noteda in9 the Batchdigit Filenumber is 729: 81 * 9 %
integer happyCount, n;
happyCountlogical :=array seen ( 0 :: 729 );
ninteger v, := 1dSum;
write(for "firsti 8:= happy0 numbers:until "729 do seen( i ) := false;
whilev happyCount < 8 do:= beginabs n;
▲ while begin
▲ logicaldSum terminated:= 0;
▲ while v not terminated and tPos <= trys0 do begin
▲ integer tPosd;
▲ trys d := v rem := -110;
▲ terminated v := falsev div 10;
▲ tPos dSum := dSum + ( d * :=d 0;)
▲ integerend while_v_ne_0 sum;
▲ dSum not = 1 terminatedand :=not seen( tPosdSum ) = number;
▲ if n < 2 then true end
▲ elsedo begin
▲ integer array seen( 0dSum ) ::= 32 )true;
▲ number v := n;dSum
end while_not_happy_and_not_looping ;
▲ numberdSum = 1
▲ end isHappy ;
begin % find the first 8 happy numbers %
▲ integer numbern, tryshCount;
hCount := 0;
▲ tPos n := tPos + 1;
▲ while hCount < end8 do begin
if isHappy( n ) then begin
writeon( i_w := 1, s_w := 0, " ", n );
happyCounthCount := happyCounthCount + 1
end if_isHappy_nif_isHappy__n ;
n := n + 1
end while_happyCount_lt_8while_hCount_lt_10
end
end.
end.</syntaxhighlight>
{{out}}
<pre>
first 8 happy numbers: 1 7 10 13 19 23 28 31
</pre>
 
Tigerofdarkness
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