Additive primes: Difference between revisions

=={{header|BCPL}}==

<lang bcpl>get "libhdr"

manifest $( limit = 500 $)

let dsum(n) =

n=0 -> 0,

dsum(n/10) + n rem 10

let sieve(prime, n) be

$( 0!prime := false

1!prime := false

for i=2 to n do i!prime := true

for i=2 to n/2

if i!prime

$( let j=i+i

while j<=n

$( j!prime := false

j := j+i

$)

$)

$)

let additive(prime, n) = n!prime & dsum(n)!prime

let start() be

$( let prime = vec limit

let num = 0

sieve(prime, limit)

for i=2 to limit

if additive(prime,i)

$( writed(i,5)

num := num + 1

if num rem 10 = 0 then wrch('*N')

$)

writef("*N*NFound %N additive primes < %N.*N", num, limit)

$)</lang>

{{out}}

<pre> 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 < 500.</pre>