前言

C语言是大多数小白走上程序员道路的第一步，在了解基础语法后，你就可以来尝试解决以下的题目。放心，本系列的文章都对新手非常友好。

Tips：题目是英文的，但我相信你肯定能看懂

一、四则运算题目

(Math tutor) Write a program that displays a menu as shown in the sample run. You can enter 1, 2, 3, or 4 for choosing an addition, subtraction, multiplication, or division test. After a test is finished, the menu is redisplayed. You may choose another test or enter 5 to exit the system. Each test generates two random single-digit numbers to form a question for addition, subtraction, multiplication, or division. For a subtraction such as number1 – number2, number1 is greater than or equal to number2. For a division question such as number1 / number2, number2 is not zero.

<Output>

Main menu

1: Addition

2: Subtraction

3: Multiplication

4: Division

5: Exit

Enter a choice: 1<enter icon>

What is 1 + 7? 8<enter icon>

Correct

Main menu

1: Addition

2: Subtraction

3: Multiplication

4: Division

5: Exit

Enter a choice: 1<enter icon>

What is 4 + 0? 5<enter icon>

Your answer is wrong. The correct answer is 4

Main menu

1: Addition

2: Subtraction

3: Multiplication

4: Division

5: Exit

Enter a choice: 4<enter icon>

What is 4 / 5? 1<enter icon>

Your answer is wrong. The correct answer is 0

Main menu

1: Addition

2: Subtraction

3: Multiplication

4: Division

5: Exit

Enter a choice:

<End Output>

二、代码示例

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

int ranNum (void);
void printIn (int);

int main()
{
    int a,n1,n2,c;
    while(a!=5)
    {
        n1=ranNum ();
        n2=ranNum ();
        printf("Main menu\n1: Addition\n2: Subtraction\n3: Multiplication\n4: Division\n5: Exit\nEnter a choice: ");
        scanf("%d",&a);
        if (a==1)
        {
            printf("What is %d + %d?",n1,n2);
            c=n1+n2;
            printIn (c);
        }
        if (a==2)
        {
            printf("What is %d - %d?",n1,n2);
            while (n1<n2)
            {
                n1=ranNum ();
            }
            c=n1-n2;
            printIn(c);
        }
        if (a==3)
        {
            printf("What is %d * %d?",n1,n2);
            c=n1*n2;
            printIn(c);
        }
        if (a==4)
        {
            printf("What is %d / %d?",n1,n2);
            while (n2==0)
            {
                n2=ranNum ();
            }
            c=n1/n2;
            printIn(c);
        }
    }
    return 0;
}

    int ranNum ()
    {
        int n;
        srand (time(NULL)+rand());
        n=rand()%10;
        return (n);
    }
    void printIn(int c)
    {
        int b;
        scanf("%d",&b);
        if (b==c)
            printf("Correct\n\n");
        else
            printf("Your answer is wrong. The correct answer is %d\n\n",c);
    }