26 lines
654 B
Julia
26 lines
654 B
Julia
function negbase(n, b)
|
|
if n == 0 return "0" end
|
|
out = IOBuffer()
|
|
while n != 0
|
|
n, r = divrem(n, b)
|
|
if r < 0
|
|
n += 1
|
|
r -= b
|
|
end
|
|
print(out, r)
|
|
end
|
|
return reverse(String(out))
|
|
end
|
|
|
|
invnegbase(nst, b) = sum((ch - '0') * b ^ (i - 1) for (i, ch) in enumerate(reverse(nst)))
|
|
|
|
testset = Dict(
|
|
(10, -2) => "11110",
|
|
(143, -3) => "21102",
|
|
(15, -10) => "195")
|
|
|
|
for ((num, base), rst) in testset
|
|
encoded = negbase(num, base)
|
|
decoded = invnegbase(encoded, base)
|
|
println("\nencode $num in base $base:\n-> expected: $rst\n-> resulted: $encoded\n-> decoded: $decoded")
|
|
end
|