add: new input scanning exercises

23-input-scanning/exercises/06-log-parser/log.txt

@@ -0,0 +1,6 @@
+learngoprogramming.com 10
+learngoprogramming.com 10
+golang.org 4
+golang.org 6
+blog.golang.org 20
+blog.golang.org 10

23-input-scanning/exercises/06-log-parser/log_err_missing.txt

@@ -0,0 +1,6 @@
+learngoprogramming.com 10
+learngoprogramming.com 10
+golang.org
+golang.org 6
+blog.golang.org 20
+blog.golang.org 10

23-input-scanning/exercises/06-log-parser/log_err_negative.txt

@@ -0,0 +1,6 @@
+learngoprogramming.com 10
+learngoprogramming.com 10
+golang.org -100
+golang.org 6
+blog.golang.org 20
+blog.golang.org 10

23-input-scanning/exercises/06-log-parser/log_err_str.txt

@@ -0,0 +1,6 @@
+learngoprogramming.com 10
+learngoprogramming.com 10
+golang.org FOUR
+golang.org 6
+blog.golang.org 20
+blog.golang.org 10

23-input-scanning/exercises/06-log-parser/main.go

@@ -0,0 +1,41 @@
+package main
+
+// ---------------------------------------------------------
+// EXERCISE: Log Parser from Stratch
+//
+//  You've watched the lecture. Now, try to create the same
+//  log parser program on your own. Do not look at the lecture,
+//  and the existing source code.
+//
+//
+// EXPECTED OUTPUT
+//
+//  go run main.go < log.txt
+//
+//   DOMAIN                             VISITS
+//   ---------------------------------------------
+//   blog.golang.org                        30
+//   golang.org                             10
+//   learngoprogramming.com                 20
+//
+//   TOTAL                                  60
+//
+//
+//  go run main.go < log_err_missing.txt
+//
+//   wrong input: [golang.org] (line #3)
+//
+//
+//  go run main.go < log_err_negative.txt
+//
+//   wrong input: "-100" (line #3)
+//
+//
+//  go run main.go < log_err_str.txt
+//
+//   wrong input: "FOUR" (line #3)
+//
+// ---------------------------------------------------------
+
+func main() {
+}