fixed bug where real numbers crashed app

answer.txt

@@ -0,0 +1,46 @@
+UPC
+200033148770
+200042041350
+200042041400
+200042064910
+200047796200
+200059594110
+200059660970
+200065290180
+200065290220
+200065290310
+200065290340
+200065290370
+200066707320
+200069556670
+200072791220
+0075849385857
+200072791320
+200072791380
+200072791470
+200072950140
+200079186270
+200079343740
+200081451640
+200081630310
+200106953220
+200156488680
+200157056340
+200168095820
+200168979440
+200172490020
+200177334550
+200177780700
+200177788230
+327582805540
+337582889920
+357582840140
+357582843530
+357582850030
+477039522210
+477039522200
+482000077030
+482000077040
+482000077090
+647582802920
+647582804700

examplelist.txt

@@ -14,6 +14,7 @@ UPC
 2.0006670732e+11
 2.0006955667e+11
 2.0007279122e+11
+0075849385857
 2.0007279132e+11
 2.0007279138E+11
 2.0007279147E+11

isNumeric.go

@@ -0,0 +1,10 @@
+package main
+
+import (
+	"regexp"
+)
+
+func isNumeric(s string) bool {
+	match, _ := regexp.MatchString("^[0-9]+$", s)
+	return match
+}

main.go

@@ -78,6 +78,11 @@ func main() {
 			continue
 		}
 
+		if isNumeric(upc) == true {
+			gtins = append(gtins, upc)
+			continue
+		}
+
 		// Lower case the E
 		upc = strings.ToLower(upc)
 		// Split scientific notation at the e+ point