Files
2019-10-30 19:41:13 +03:00

80 lines
1.7 KiB
Go

// Copyright © 2018 Inanc Gumus
// Learn Go Programming Course
// License: https://creativecommons.org/licenses/by-nc-sa/4.0/
//
// For more tutorials : https://learngoprogramming.com
// In-person training : https://www.linkedin.com/in/inancgumus/
// Follow me on twitter: https://twitter.com/inancgumus
package main
import (
"bufio"
"fmt"
"os"
"sort"
"strconv"
"strings"
)
func main() {
var (
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
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, lines)
return
}
domain := fields[0]
// Sum the total visits per domain
visits, err := strconv.Atoi(fields[1])
if visits < 0 || err != nil {
fmt.Printf("wrong input: %q (line #%d)\n", fields[1], lines)
return
}
// Collect the unique domains
if _, ok := sum[domain]; !ok {
domains = append(domains, domain)
}
// Keep track of total and per domain visits
total += visits
sum[domain] += visits
}
// Print the visits per domain
sort.Strings(domains)
fmt.Printf("%-30s %10s\n", "DOMAIN", "VISITS")
fmt.Println(strings.Repeat("-", 45))
for _, domain := range domains {
visits := sum[domain]
fmt.Printf("%-30s %10d\n", domain, visits)
}
// Print the total visits for all domains
fmt.Printf("\n%-30s %10d\n", "TOTAL", total)
// Let's handle the error
if err := in.Err(); err != nil {
fmt.Println("> Err:", err)
}
}