Add solution for Challenge 6 by hudazaan

challenge-6/submissions/hudazaan/solution-template.go

@@ -0,0 +1,43 @@
+package challenge6
+
+import (
+	"strings"
+	"unicode"
+)
+
+// CountWordFrequency takes a string containing multiple words and returns
+// a map where each key is a word and the value is the number of times that
+// word appears in the string. The comparison is case-insensitive.
+func CountWordFrequency(text string) map[string]int {
+	frequency := make(map[string]int)
+
+	if text == "" {
+		return frequency
+	}
+
+	var currentWord strings.Builder
+
+	for _, char := range text {
+		if unicode.IsLetter(char) || unicode.IsDigit(char) {
+			currentWord.WriteRune(unicode.ToLower(char))
+		} else if char == '\'' {
+			// ignore apostrophes (do nothing)
+			continue
+		} else {
+			// word boundary
+			if currentWord.Len() > 0 {
+				word := currentWord.String()
+				frequency[word]++
+				currentWord.Reset()
+			}
+		}
+	}
+
+	// handle last word if exists
+	if currentWord.Len() > 0 {
+		word := currentWord.String()
+		frequency[word]++
+	}
+
+	return frequency
+}