Additive primes: Difference between revisions

=={{header|FutureBasic}}==

<syntaxhighlight lang="futurebasic">

local fn IsPrime( n as NSUInteger ) as BOOL

NSUInteger i

BOOL result = YES

if ( n < 2 ) then exit fn = NO

for i = 2 to n + 1

if ( i * i <= n ) and ( n mod i == 0 )

exit fn = NO

end if

next

end fn = result

local fn DigSum( n as NSUInteger ) as NSUInteger

NSUInteger s = 0

while ( n > 0 )

s += ( n mod 10 )

n /= 10

wend

end fn = s

void local fn AdditivePrimes( n as NSUInteger )

NSUInteger i, s = 0, counter = 0

printf @"Additive Primes:"

for i = 2 to n

if ( fn IsPrime(i) ) and ( fn IsPrime( fn DigSum(i) ) )

s++

printf @"%4ld \b", i : counter++

if counter == 10 then counter = 0 : print

end if

next

printf @"\n\nFound %lu additive primes less than %lu.", s, n

end fn

fn AdditivePrimes( 500 )

HandleEvents

</syntaxhighlight>

{{output}}

<pre>

Additive Primes:

2 3 5 7 11 23 29 41 43 47

61 67 83 89 101 113 131 137 139 151

157 173 179 191 193 197 199 223 227 229

241 263 269 281 283 311 313 317 331 337

353 359 373 379 397 401 409 421 443 449

461 463 467 487

Found 54 additive primes less than 500.

</pre>