fix: log parser project

23-project-log-parser/02-project-log-parser/main.go

@@ -11,54 +11,63 @@ import (
 	"bufio"
 	"fmt"
 	"os"
+	"sort"
 	"strconv"
 	"strings"
 )
 
 func main() {
 	var (
-		// Stores the visits per unique domain
-		sum = make(map[string]int)
-
-		// Stores the unique domain names for printing
-		domains []string
-
-		in = bufio.NewScanner(os.Stdin)
+		sum     map[string]int // total visits per domain
+		domains []string       // unique domain names
+		total   int            // total visits to all domains
+		lines   int            // number of parsed lines (for the error messages)
 	)
 
+	sum = make(map[string]int)
+
 	// Scan the standard-in line by line
-	for line := 1; in.Scan(); line++ {
+	in := bufio.NewScanner(os.Stdin)
+	for in.Scan() {
+		lines++
+
 		// Parse the fields
 		fields := strings.Fields(in.Text())
 		if len(fields) != 2 {
-			fmt.Printf("wrong input: %v (line #%d)\n", fields, line)
+			fmt.Printf("wrong input: %v (line #%d)\n", fields, lines)
 			return
 		}
-		domain, visits := fields[0], fields[1]
-
-		// Collect the unique domains
-		if _, ok := sum[domain]; !ok {
-			domains = append(domains, domain)
-		}
 
 		// Sum the total visits per domain
-		n, err := strconv.Atoi(visits)
-		if n < 0 || err != nil {
-			fmt.Printf("wrong input: %q (line #%d)\n", visits, line)
+		visits, err := strconv.Atoi(fields[1])
+		if visits < 0 || err != nil {
+			fmt.Printf("wrong input: %q (line #%d)\n", fields[1], lines)
 			return
 		}
-		sum[domain] += n
+
+		name := fields[0]
+
+		// Collect the unique domains
+		if _, ok := sum[name]; !ok {
+			domains = append(domains, name)
+		}
+
+		// Keep track of total and per domain visits
+		total += visits
+		sum[name] += visits
 	}
 
 	// Print the visits per domain
-	var total int
-	for _, domain := range domains {
-		hits := sum[domain]
+	sort.Strings(domains)
 
-		fmt.Printf("%-25s -> %d\n", domain, hits)
-		total += hits
+	fmt.Printf("%-30s %10s\n", "DOMAIN", "VISITS")
+	fmt.Println(strings.Repeat("-", 45))
+
+	for _, name := range domains {
+		visits := sum[name]
+		fmt.Printf("%-30s %10d\n", name, visits)
 	}
 
 	// Print the total visits for all domains
-	fmt.Printf("\n%-25s -> %d\n", "TOTAL", total)
+	fmt.Printf("\n%-30s %10d\n", "TOTAL", total)
 }