Source code in the clu programming language

fusc = iter () yields (int)
    q: array[int] := array[int]$[1]
    yield(0)
    yield(1)
    
    while true do
        x: int := array[int]$reml(q)
        array[int]$addh(q,x)
        yield(x)
        
        x := x + array[int]$bottom(q)
        array[int]$addh(q,x)
        yield(x)
    end
end fusc

longest_fusc = iter () yields (int,int)
    sofar: int := 0
    count: int := 0
    
    for f: int in fusc() do
        if f >= sofar then
            yield (count,f)
            sofar := 10*sofar
            if sofar=0 then sofar:=10 end
        end
        count := count + 1
    end
end longest_fusc

start_up = proc ()
    po: stream := stream$primary_output()
    
    stream$putl(po, "First 61:")
    n: int := 0
    for f: int in fusc() do
        stream$puts(po, int$unparse(f) || " ")
        n := n + 1
        if n = 61 then break end
    end
    
    stream$putl(po, "\nLength records:")
    n := 0
    for i, f: int in longest_fusc() do
        stream$putl(po, "fusc(" || int$unparse(i) || ") = " || int$unparse(f))
        n := n + 1
        if n = 5 then break end
    end
end start_up