Add solution for Challenge 6 by WHFF521 (#1890)

Auto-merged after 2 days with all checks passing.

PR: #1890
Author: @WHFF521

Author: WHFF521

challenge-6/submissions/WHFF521/solution-template.go

@@ -0,0 +1,33 @@
+// Package challenge6 contains the solution for Challenge 6.
+package challenge6
+
+import (
+	// Add any necessary imports here
+	"regexp"
+	"strings"
+)
+
+// 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.
+//
+// Words are defined as sequences of letters and digits.
+// All words are converted to lowercase before counting.
+// All punctuation, spaces, and other non-alphanumeric characters are ignored.
+//
+// For example:
+// Input: "The quick brown fox jumps over the lazy dog."
+// Output: map[string]int{"the": 2, "quick": 1, "brown": 1, "fox": 1, "jumps": 1, "over": 1, "lazy": 1, "dog": 1}
+var wordRegex = regexp.MustCompile(`[a-zA-Z0-9]+(?:'[a-zA-Z0-9]+)*`)
+func CountWordFrequency(text string) map[string]int {
+	// Your implementation here
+	words := wordRegex.FindAllString(text,-1)
+	frequencyMap := make(map[string]int)
+	
+	for _,word := range(words){
+	    lowerWord := strings.ToLower(word)
+	    lowerWord = strings.ReplaceAll(lowerWord,"'","")
+	    frequencyMap[lowerWord]++
+	}
+	return frequencyMap
+}