Add teimurjan quiz implementation (#42)

Author: teimurjan

students/teimurjan/main.go

@@ -0,0 +1,118 @@
+package main
+
+import (
+	"bufio"
+	"encoding/csv"
+	"flag"
+	"fmt"
+	"io"
+	"log"
+	"os"
+	"strings"
+	"time"
+)
+
+// Problem object
+type Problem struct {
+	Question string
+	Answer   string
+}
+
+// ValidateAnswer validates answer for the problem
+func (p *Problem) ValidateAnswer(answer string) bool {
+	return p.Answer == answer
+}
+
+// Quiz object
+type Quiz struct {
+	Problems []Problem
+	Score    int
+}
+
+func main() {
+	var file string
+	flag.StringVar(&file, "file", "problems.csv", "--file=path/to/problems/file")
+	var quizTime int
+	flag.IntVar(&quizTime, "time", 30, "--time=15")
+	flag.Parse()
+
+	WaitForStart()
+	quiz := Quiz{
+		Problems: ParseProblemsFrom(file),
+		Score:    0,
+	}
+	go func() {
+		<-time.After(time.Duration(quizTime) * time.Second)
+		ShowTimeIsUpMessage()
+		ShowFinalMessage(quiz.Score, len(quiz.Problems))
+		os.Exit(0)
+	}()
+	RunQuiz(&quiz)
+	ShowFinalMessage(quiz.Score, len(quiz.Problems))
+}
+
+// WaitForStart makes the program wait for a user to press Enter button
+func WaitForStart() {
+	fmt.Print("Press 'Enter' to start the quiz.")
+	bufio.NewReader(os.Stdin).ReadBytes('\n')
+}
+
+// ParseProblemsFrom parses problems from file by the provided path
+func ParseProblemsFrom(pathToFile string) []Problem {
+	file, err := os.Open(pathToFile)
+	if err != nil {
+		log.Fatal("File does not exists")
+	}
+	reader := csv.NewReader(bufio.NewReader(file))
+	var problems []Problem
+	for {
+		line, error := reader.Read()
+		if error == io.EOF {
+			break
+		} else if error != nil {
+			log.Fatal(error)
+		}
+		problems = append(problems, Problem{
+			Question: line[0],
+			Answer:   line[1],
+		})
+	}
+	return problems
+}
+
+// RunQuiz starts the quiz
+func RunQuiz(q *Quiz) {
+	reader := bufio.NewReader(os.Stdin)
+	for _, problem := range q.Problems {
+		AskQuestion(&problem)
+		answer := ReadLine(reader)
+		if problem.ValidateAnswer(answer) {
+			q.Score++
+		}
+	}
+}
+
+// AskQuestion asks a problem's question
+func AskQuestion(p *Problem) {
+	fmt.Print(p.Question + " ")
+}
+
+// ReadLine read a line using buifo.Reader
+func ReadLine(reader *bufio.Reader) string {
+	str, _, err := reader.ReadLine()
+	if err == io.EOF {
+		return ""
+	}
+
+	return strings.TrimRight(string(str), "\r\n")
+}
+
+// ShowTimeIsUpMessage shows time is up message
+func ShowTimeIsUpMessage() {
+	fmt.Println("\rTime is up!")
+}
+
+// ShowFinalMessage shows final message with the correctness statistics
+func ShowFinalMessage(correctAnswersCount int, problemsCount int) {
+	fmt.Printf("\rThere is/are %d correct answers given for %d problems.\n", correctAnswersCount, problemsCount)
+}

students/teimurjan/problems.csv

@@ -0,0 +1,12 @@
+5+5,10
+1+1,2
+8+3,11
+1+2,3
+8+6,14
+3+1,4
+1+4,5
+5+1,6
+2+3,5
+3+3,6
+2+4,6
+5+2,7