Proper decoding

gistfile1.diff

diff --git a/api/iteration.go b/api/iteration.go
index 49b833a..01eea02 100644
--- a/api/iteration.go
+++ b/api/iteration.go
@@ -5,6 +5,13 @@ import (
 	"io/ioutil"
 	"path/filepath"
 	"strings"
+
+	"golang.org/x/net/html/charset"
+	"golang.org/x/text/transform"
+)
+
+const (
+	mimeType = "text/plain"
 )
 
 var (
@@ -53,12 +60,13 @@ func NewIteration(dir string, filenames []string) (*Iteration, error) {
 	iter.Problem = segments[2]
 
 	for _, filename := range filenames {
-		b, err := ioutil.ReadFile(filename)
+		fileContents, err := readFileAsUTF8String(filename)
 		if err != nil {
 			return nil, err
 		}
+
 		path := filename[len(iter.RelativePath()):]
-		iter.Solution[path] = string(b)
+		iter.Solution[path] = *fileContents
 	}
 	return iter, nil
 }
@@ -73,3 +81,21 @@ func (iter *Iteration) isValidFilepath(path string) bool {
 	}
 	return strings.HasPrefix(strings.ToLower(path), strings.ToLower(iter.Dir))
 }
+
+func readFileAsUTF8String(filename string) (*string, error) {
+	b, err := ioutil.ReadFile(filename)
+	if err != nil {
+		return nil, err
+	}
+
+	encoding, _, _ := charset.DetermineEncoding(b, mimeType)
+	decoder := encoding.NewDecoder()
+
+	decodedBytes, _, err := transform.Bytes(decoder, b)
+	if err != nil {
+		return nil, err
+	}
+
+	s := string(decodedBytes)
+	return &s, nil
+}