random-name-selection.go

package main

import (
	"bufio"
	"fmt"
	"log"
	"math/rand"
	"os"
	"sort"
	"strconv"
	"time"

	"github.com/olekukonko/tablewriter"
)

func main() {
	names := FetchNames()
	rand.Seed(time.Now().UnixNano())
	const loops = 2023

	frequency := make(map[string]int)
	for i := 0; i < loops; i++ {
		frequency[names[rand.Intn(len(names))]]++
	}

	PrintResults(os.Stdout, frequency, loops)
}

func PrintResults(output *os.File, frequency map[string]int, loops int) {
	var namesAndCounts [][]string
	for name, count := range frequency {
		namesAndCounts = append(namesAndCounts, []string{name, fmt.Sprintf("%d", count)})
	}

	sort.Slice(namesAndCounts, func(i, j int) bool {
		return namesAndCounts[i][1] > namesAndCounts[j][1]
	})

	table := tablewriter.NewWriter(output)
	table.SetHeader([]string{"S/N", "Name", "Count", "Percentage"})

	for i, nameAndCount := range namesAndCounts {
		count, _ := strconv.Atoi(nameAndCount[1])
		percentage := float64(count) / float64(loops) * 100

		line := []string{fmt.Sprintf("%d", i+1), nameAndCount[0], nameAndCount[1], fmt.Sprintf("%.2f%%", percentage)}
		table.Append(line)
	}

	table.Render()
}

func FetchNames() []string {
	file, err := os.Open("names.txt")
	if err != nil {
		log.Fatalf("failed to open")
	}
	defer file.Close()

	scanner := bufio.NewScanner(file)
	scanner.Split(bufio.ScanLines)

	var names []string
	for scanner.Scan() {
		names = append(names, scanner.Text())
	}

	return names
}