四则运算

主要功能：实现小学生四则运算的功能。

设计思想：考虑到小学生的运算能力，可以让小学生自己选择四则运算的种类，以及运算的位数，答完题后，系统自动判断对错。

#include <stdio.h>

#include <stdlib.h>
#include <time.h>
int add(int num1,int num2)//加法
{
 return num1+num2;
}
int subtraction(int num1,int num2)//减法
{
 return num1-num2;
}
int mul(int num1,int num2)//乘法
{
 return num1*num2;
}
float divis(int num1,int num2)//除法
{
 return ((int)(((float)num1/num2)*100+0.5))/100.0;
}
int main()
{ 
 int type = -1;
 int data = -1;
 int choice,num1,num2,results;
 float div_result;
 int right = 0;
 int wrong = 0;
 char ch;
 printf("欢迎进入四则运算题，现在开始爆发你的小宇宙吧！
");
 srand((unsigned int)time(NULL));
 while(1)
 {
  printf("请选择运算类型：1.加法  2.减法  3.乘法  4.除法(保留两位小数)
");
  scanf("%d",&choice);
  printf("请选择位数：1.一位数  2.两位数
");
  scanf("%d",&data);
  switch (choice)
  {
  case 1:
   if(data == 1)
   {
    num1 = rand()%10;
    num2 = rand()%10;
    printf("%d + %d=__?__
",num1,num2);
    scanf("%d",&results);
    if(results == add(num1,num2))
    {
     printf("回答正确！
");
     right++;
    }
    else
    {
     printf("回答错误！
");
     wrong++;
    }
    printf("是否继续？y/n
");
    getchar();
    scanf("%c",&ch);
    if(ch == 'y')
     break;
    else if(ch == 'n')
     goto end;
   }
   else if (data == 2)
   {
    num1 = rand()%100;
    num2 = rand()%100;
    printf("%d + %d=__?__
",num1,num2);
    scanf("%d",&results);
    if(results == add(num1,num2))
    {
     printf("回答正确！
");
     right++;
    }
    else
    {
     printf("回答错误！
");
     wrong++;
    }
    printf("是否继续？y/n
");
    getchar();
    scanf("%c",&ch);
    if(ch == 'y')
     break;
    else if(ch == 'n')
     goto end;
   }
   break;
  case 2:
   if(data == 1)
   {
    num1 = rand()%10;
    num2 = rand()%10;
    printf("%d - %d=__?__
",num1,num2);
    scanf("%d",&results);
    if(results == subtraction(num1,num2))
    {
     printf("回答正确！
");
     right++;
    }
    else
    {
     printf("回答错误！
");
     wrong++;
    }
    printf("是否继续？y/n
");
    getchar();
    scanf("%c",&ch);
    if(ch == 'y')
     break;
    else if(ch == 'n')
     goto end;
   }
   else if (data == 2)
   {
    num1 = rand()%100;
    num2 = rand()%100;
    printf("%d - %d=__?__
",num1,num2);
    scanf("%d",&results);
    if(results == subtraction(num1,num2))
    {
     printf("回答正确！
");
     right++;
    }
    else
    {
     printf("回答错误！
");
     wrong++;
    }
    printf("是否继续？y/n
");
    getchar();
    scanf("%c",&ch);
    if(ch == 'y')
     break;
    else if(ch == 'n')
     goto end;
   }
   break;
  case 3:
   if(data == 1)
   {
    num1 = rand()%10;
    num2 = rand()%10;
    printf("%d * %d=__?__
",num1,num2);
    scanf("%d",&results);
    if(results == mul(num1,num2))
    {
     printf("回答正确！
");
     right++;
    }
    else
    {
     printf("回答错误！
");
     wrong++;
    }
    printf("是否继续？y/n
");
    getchar();
    scanf("%c",&ch);
    if(ch == 'y')
     break;
    else if(ch == 'n')
     goto end;
   }
   else if (data == 2)
   {
    num1 = rand()%100;
    num2 = rand()%100;
    printf("%d * %d=__?__
",num1,num2);
    scanf("%d",&results);
    if(results == mul(num1,num2))
    {
     printf("回答正确！
");
     right++;
    }
    else
    {
     printf("回答错误！
");
     wrong++;
    }
    printf("是否继续？y/n
");
    getchar();
    scanf("%c",&ch);
    if(ch == 'y')
     break;
    else if(ch == 'n')
     goto end;
   }
   break;
  case 4:
   if(data == 1)
   {
    num1 = rand()%10;
    num2 = rand()%10+1;
    printf("%d / %d=__?__
",num1,num2);
    scanf("%f",&div_result);
    if(div_result == divis(num1,num2))
    {
     printf("回答正确！
");
     right++;
    }
    else
    {
     printf("回答错误！
");
     wrong++;
    }
    printf("是否继续？y/n
");
    getchar();
    scanf("%c",&ch);
    if(ch == 'y')
     break;
    else if(ch == 'n')
     goto end;
   }
   else if (data == 2)
   {
    num1 = rand()%100;
    num2 = rand()%100+1;
    printf("%d / %d=__?__
",num1,num2);
    scanf("%f",&div_result);
    if(div_result == divis(num1,num2))
    {
     printf("回答正确！
");
     right++;
    }
    else
    {
     printf("回答错误！
");
     wrong++;
    }
    printf("是否继续？y/n
");
    getchar();
    scanf("%c",&ch);
    if(ch == 'y')
     break;
    else if(ch == 'n')
     goto end;
   }
   break;
  default :
   printf("输入错误！
");
   break;
  }
 }
end:
 printf("回答正确%d题，回答错误%d题
",right,wrong);
 printf("
====================谢谢光临====================！
");
 system("pause");
 return 0;
}























总结：通过这次完成实现自动生成小学四则运算题目的程序，我意识到我的C语言的基础知识还是不扎实，在老师和同学的帮助下才完成的这个项目，所以，在以后的学习中，我还要不断地继续努力，上课多提问，多去查阅相关资料的书籍，使自己不断的进步。