Add length-of-last-word

Author: tinycedar

Diff for: length-of-last-word.go

@@ -0,0 +1,28 @@
+package main
+
+import (
+	"fmt"
+)
+
+func main() {
+	fmt.Println(lengthOfLastWord("a"))
+	fmt.Println(lengthOfLastWord("abc   "))
+	fmt.Println(lengthOfLastWord("   abc"))
+}
+
+func lengthOfLastWord(s string) int {
+	length := len(s)
+	spacePos := -1
+	nonSpacePos := -1
+	for i := length - 1; i >= 0; i-- {
+		if s[i] != ' ' {
+			if nonSpacePos < 0 {
+				nonSpacePos = i
+			}
+		} else if nonSpacePos >= 0 {
+			spacePos = i
+			break
+		}
+	}
+	return nonSpacePos - spacePos
+}