Data commit

Task/Display-a-linear-combination/Go/display-a-linear-combination.go

@@ -0,0 +1,59 @@
+package main
+
+import (
+    "fmt"
+    "strings"
+)
+
+func linearCombo(c []int) string {
+    var sb strings.Builder
+    for i, n := range c {
+        if n == 0 {
+            continue
+        }
+        var op string
+        switch {
+        case n < 0 && sb.Len() == 0:
+            op = "-"
+        case n < 0:
+            op = " - "
+        case n > 0 && sb.Len() == 0:
+            op = ""
+        default:
+            op = " + "
+        }
+        av := n
+        if av < 0 {
+            av = -av
+        }
+        coeff := fmt.Sprintf("%d*", av)
+        if av == 1 {
+            coeff = ""
+        }
+        sb.WriteString(fmt.Sprintf("%s%se(%d)", op, coeff, i+1))
+    }
+    if sb.Len() == 0 {
+        return "0"
+    } else {
+        return sb.String()
+    }
+}
+
+func main() {
+    combos := [][]int{
+        {1, 2, 3},
+        {0, 1, 2, 3},
+        {1, 0, 3, 4},
+        {1, 2, 0},
+        {0, 0, 0},
+        {0},
+        {1, 1, 1},
+        {-1, -1, -1},
+        {-1, -2, 0, -3},
+        {-1},
+    }
+    for _, c := range combos {
+        t := strings.Replace(fmt.Sprint(c), " ", ", ", -1)
+        fmt.Printf("%-15s  ->  %s\n", t, linearCombo(c))
+    }
+}