tasks a-s

Task/Polynomial-long-division/Go/polynomial-long-division.go

@@ -0,0 +1,46 @@
+package main
+
+import "fmt"
+
+func main() {
+    n := []float64{-42, 0, -12, 1}
+    d := []float64{-3, 1}
+    fmt.Println("N:", n)
+    fmt.Println("D:", d)
+    q, r, ok := pld(n, d)
+    if ok {
+        fmt.Println("Q:", q)
+        fmt.Println("R:", r)
+    } else {
+        fmt.Println("error")
+    }
+}
+
+func degree(p []float64) int {
+    for d := len(p) - 1; d >= 0; d-- {
+        if p[d] != 0 {
+            return d
+        }
+    }
+    return -1
+}
+
+func pld(nn, dd []float64) (q, r []float64, ok bool) {
+    if degree(dd) < 0 {
+        return
+    }
+    nn = append(r, nn...)
+    if degree(nn) >= degree(dd) {
+        q = make([]float64, degree(nn)-degree(dd)+1)
+        for degree(nn) >= degree(dd) {
+            d := make([]float64, degree(nn)+1)
+            copy(d[degree(nn)-degree(dd):], dd)
+            q[degree(nn)-degree(dd)] = nn[degree(nn)] / d[degree(d)]
+            for i := range d {
+                d[i] *= q[degree(nn)-degree(dd)]
+                nn[i] -= d[i]
+            }
+        }
+    }
+    return q, nn, true
+}