Initial data commit

Task/CUSIP/Go/cusip.go

@@ -0,0 +1,50 @@
+package main
+
+import "fmt"
+
+func isCusip(s string) bool {
+    if len(s) != 9 { return false }
+    sum := 0
+    for i := 0; i < 8; i++ {
+        c := s[i]
+        var v int
+        switch {
+            case c >= '0' && c <= '9':
+                v = int(c) - 48
+            case c >= 'A' && c <= 'Z':
+                v = int(c) - 55
+            case c == '*':
+                v = 36
+            case c == '@':
+                v = 37
+            case c == '#':
+                v = 38
+            default:
+                return false
+        }
+        if i % 2 == 1 { v *= 2 }  // check if odd as using 0-based indexing
+        sum += v/10 + v%10
+    }
+    return int(s[8]) - 48 == (10 - (sum%10)) % 10
+}
+
+func main() {
+    candidates := []string {
+        "037833100",
+        "17275R102",
+        "38259P508",
+        "594918104",
+        "68389X106",
+        "68389X105",
+    }
+
+    for _, candidate := range candidates {
+        var b string
+        if isCusip(candidate) {
+            b = "correct"
+        } else {
+            b = "incorrect"
+        }
+        fmt.Printf("%s -> %s\n", candidate, b)
+    }
+}