calc_game.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>

int addition(char *s)
{
    int x = ((unsigned)rand() % 99) + 1;
    int y = ((unsigned)rand() % 99) + 1;
    sprintf(s, "%d + %d = ", x, y);
    return x + y;
}

int subtraction(char *s)
{
    int x, y;
    while (1) {
        x = ((unsigned)rand() % 99) + 1;
        y = ((unsigned)rand() % 99) + 1;
        if (x > y) {
            break;
        }
    }
    sprintf(s, "%d - %d = ", x, y);
    return x - y;
}

int multiplication(char *s)
{
    int x = ((unsigned)rand() % 9) + 1;
    int y = ((unsigned)rand() % 9) + 1;
    sprintf(s, "%d x %d = ", x, y);
    return x * y;
}

int division(char *s)
{
    int x = ((unsigned)rand() % 9) + 1;
    int y = ((unsigned)rand() % 9) + 1;
    sprintf(s, "%d / %d = ", x*y, y);
    return x;
}

int main(int argc, char *argv[])
{
    int (*funcp[])(char *s) = {addition, subtraction, multiplication, division};
    int correct;
    int answer;
    char question[64];
    char buf[64];
    srand((unsigned)time(NULL));
    while (1) {
        memset(question, 0x0, sizeof(question));
        correct = (*funcp[rand() % 4])(question);
        while (1) {
            printf("%s", question);
            scanf("%s", buf);
            answer = atoi(buf);
            if (answer == correct) {
                break;
            }
        }
    }
    return 0;
}

calc_game.go

package main

import (
	"fmt"
	"math/rand"
	"os"
	"strconv"
	"time"
)

type Calc interface {
	GetQuestion() string
	GetCorrect() int
}

type Addition struct {
	x, y int
}

func NewAddition() *Addition {
	addition := new(Addition)
	rand.Seed(time.Now().UnixNano())
	addition.x = rand.Intn(10)
	addition.y = rand.Intn(10)
	return addition
}

func (addition *Addition) GetQuestion() string {
	return fmt.Sprintf("%d + %d = ", addition.x, addition.y)
}

func (addition *Addition) GetCorrect() int {
	return addition.x + addition.y
}

type Subtraction struct {
	x, y int
}

func NewSubtraction() *Subtraction {
	subtraction := new(Subtraction)
	rand.Seed(time.Now().UnixNano())
	for {
		x := rand.Intn(10)
		y := rand.Intn(10)
		if x > y {
			subtraction.x = x
			subtraction.y = y
			break
		}
	}
	return subtraction
}

func (subtraction *Subtraction) GetQuestion() string {
	return fmt.Sprintf("%d - %d = ", subtraction.x, subtraction.y)
}

func (subtraction *Subtraction) GetCorrect() int {
	return subtraction.x - subtraction.y
}

func main() {
	var calc Calc
	rand.Seed(time.Now().UnixNano())
	for {
		i := rand.Intn(2)
		if i == 0 {
			calc = NewAddition()
		} else {
			calc = NewSubtraction()
		}
		for {
			fmt.Print(calc.GetQuestion())
			var s string
			fmt.Scanf("%s\n", &s)
			if s == "q" {
				os.Exit(0)
			}
			a, _ := strconv.Atoi(s)
			if a == calc.GetCorrect() {
				fmt.Println("correct")
				break
			} else {
				fmt.Println("incorrect")
			}
		}
	}
}

calc_game.html

<form name="test" action="#">
<div id="question"></div>
<input type="text" name="answer">
<input type="button" value="?" onclick="func()">
<div id="answer"></div>
</form>
<script>
  class Addition {
    constructor() {
      this.x = Math.ceil(Math.random() * 9);
      this.y = Math.ceil(Math.random() * 9);
    }
    question() {
      return this.x + " + " + this.y + " = ";
    }
    correct() {
      return this.x + this.y;
    }
  }
  var addition = new Addition();
  document.getElementById("question").innerHTML = addition.question();
  function func() {
    var answer = parseFloat(document.test.answer.value)
    alert((answer == addition.correct() ? "correct" : "incorrect"))
  }
</script>

calc_game.py

#!/usr/bin/env python

import sys
import random

class Addition:
    def __init__(self):
        self.x = random.randint(1, 10)
        self.y = random.randint(1, 10)

    def question(self):
        return str(self.x) + ' + ' + str(self.y) + ' = '

    def correct(self):
        return self.x + self.y

class Subtraction:
    def __init__(self):
        while True:
            self.x = random.randint(1, 10)
            self.y = random.randint(1, 10)
            if self.x > self.y:
                break

    def question(self):
        return str(self.x) + ' - ' + str(self.y) + ' = '

    def correct(self):
        return self.x - self.y

def main():
    calc_class_list = ['Addition', 'Subtraction']
    while True:
        random.shuffle(calc_class_list)
        calc = globals()[calc_class_list[0]]()
        while True:
            print(calc.question(), end='')
            s = input()
            if s == 'q':
                sys.exit(0)
            if int(s) == calc.correct():
                print('正解')
                break
            else:
                print('不正解')

if __name__ == '__main__':
    main()

calc_game.rb

#!/usr/bin/env ruby

class Addition
  def initialize
    random = Random.new
    @x = random.rand(1..99)
    @y = random.rand(1..99)
  end
  def question
    "#{@x} + #{@y} = "
  end
  def correct
    @x + @y
  end
end

class Subtraction
  def initialize
    random = Random.new
    while true
      @x = random.rand(1..99)
      @y = random.rand(1..99)
      break if @x > @y
    end
  end
  def question
    "#{@x} - #{@y} = "
  end
  def correct
    @x - @y
  end
end

class Multiplication
  def initialize
    random = Random.new
    @x = random.rand(1..9)
    @y = random.rand(1..9)
  end
  def question
    "#{@x} x #{@y} = "
  end
  def correct
    @x * @y
  end
end

while true
  q = [Addition, Subtraction, Multiplication].shuffle.first.new
  while true
    print q.question
    answer = $stdin.gets.strip.to_i
    break if answer == q.correct
  end
end