Add wbgalvao solution (#19)

Author: wbgalvao

students/wbgalvao/main.go

@@ -0,0 +1,82 @@
+package main
+
+import (
+	"encoding/csv"
+	"flag"
+	"fmt"
+	"log"
+	"os"
+	"time"
+)
+
+type question struct {
+	problem string
+	result  string
+}
+
+type quiz struct {
+	questions []question
+	score     int
+}
+
+func (q *quiz) ask() {
+	q.score = 0
+	for _, question := range q.questions {
+		fmt.Println(question.problem)
+		var answer string
+		fmt.Scanln(&answer)
+		if answer == question.result {
+			q.score++
+		}
+	}
+}
+
+func readCSV(p string) []question {
+	qfile, err := os.Open(p)
+	if err != nil {
+		log.Fatalf("could not open file: %v\n", err)
+	}
+	defer qfile.Close()
+	csvrd := csv.NewReader(qfile)
+	records, err := csvrd.ReadAll()
+	if err != nil {
+		log.Fatalf("could not parse .csv: %v\n", err)
+	}
+	var questions []question
+	for _, record := range records {
+		q := question{problem: record[0], result: record[1]}
+		questions = append(questions, q)
+	}
+	return questions
+}
+
+var (
+	qCSV    string
+	timeout int
+)
+
+func init() {
+	flag.StringVar(&qCSV, "quiz", "", "A .csv file with questions and answers.")
+	flag.IntVar(&timeout, "timeout", 30, "The time limit for answering questions.")
+	flag.Parse()
+}
+
+func main() {
+	if qCSV == "" {
+		log.Fatalln("a .csv file must be provided through the -quiz flag")
+	}
+	questions := readCSV(qCSV)
+	qz := quiz{questions: questions, score: 0}
+	timeoutCh := time.After(time.Duration(timeout) * time.Second)
+	resultCh := make(chan quiz)
+	go func() {
+		qz.ask()
+		resultCh <- qz
+	}()
+	select {
+	case <-resultCh:
+	case <-timeoutCh:
+		fmt.Println("Timeout!")
+	}
+	fmt.Println("Score: ", qz.score)
+}