sidef/scripts/RosettaCode/polynomial_synthetic_division.sf

#!/usr/bin/ruby

#
## https://rosettacode.org/wiki/Polynomial_synthetic_division
#

func extended_synthetic_division(dividend, divisor) {
    var end = divisor.end
    var out = dividend.clone
    var normalizer = divisor[0]

    for i in ^(dividend.len - end) {
        out[i] /= normalizer
        var coef = -out[i]
        if (coef != 0) {
            for j in (1 .. end) {
                out[i+j] += divisor[j]*coef
            }
        }
    }

    var remainder = out.splice(-end)
    var quotient = out

    return(quotient, remainder)
}

var (n, d) = ([1, -12, 0, -42], [1, -3])
var (q, r) = extended_synthetic_division(n, d)

print("  %s / %s =" % (n, d))
print(" %s remainder %s\n" % (q, r))

assert_eq(q, [1, -9, -27])
assert_eq(r, [-123])