sieve.rap

fun SIEVE (N)
    PRIME:= <* yes *> * N

    for K from 2 to sqrt(N)+0.5 do
        if PRIME[K] then
            for J from K+K to N step K do
                PRIME[J]:= no
            od
        fi
    od
    PRIME_NUMBERS:= <* *>
    for K from 2 to N do
        if PRIME[K] then
            PRIME_NUMBERS:= PRIME_NUMBERS + <* K *>
        fi
    od
    return PRIME_NUMBERS
end

output: SIEVE(5)
output: SIEVE(200)