| 这个作业属于那个课程 | https://edu.cnblogs.com/campus/zswxy/CST2019-4/homework/10269 |
|---|---|
| 这个作业要求在哪里 | https://edu.cnblogs.com/campus/zswxy/CST2019-4/homework/10269 |
| 这个作业的目标是 | 熟悉用函数和switch语句编程口算题菜单，还有随机数rand的使用，并算出生成口算题的结果 |
| 作业正文 | 在上次作业中加个答案函数即可，生成随机数的结果 |
| 参考文献 | https://zhidao.baidu.com/question/271899014.html，百度c语言中%g的使用和含义 |
2.2.2设计思路和遇到的问题
设计思路：和前面的第三次作业相似，添加答案函数即可。
遇到的问题：不知道生成答案，还有%g的意思不理解。
2.2.3程序结果截图
2.2.4程序代码
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <string.h>
void menu();
void help();
void one();void operation_1();
void two();void operation_2();
void three();void operation_3();
void error();
int main()
{
int i=1,n;
printf("==========口算生成器==========
");
printf("欢迎使用口算生成器:
");
printf("
");
help();
while(i!=0)
{
menu();
printf("请输入操作> ");
scanf("%d",&i);
printf("<执行操作:)
");
printf("
");
switch(i)
{
case 1:operation_1();break;
case 2:operation_2();break;
case 3:operation_3();break;
case 4:help();break;
case 5:printf("程序结束, 欢迎下次使用
");
printf("任意键结束……");
i=0;
default:error();break;
}
}
return 0;
}
void menu()
{
printf("
");
printf("操作列表:
");
printf("1)一年级 2)二年级 3)三年级
");
printf("4)帮助 5)退出程序
");
}
void help()
{
printf("
");
printf("帮助信息
");
printf("您需要输入命令代号来进行操作,且
");
printf("一年级题目为不超过十位的加减法
二年级题目为不超过百位的乘除法
三年级题目为不超过百位的加减乘除混合题目
");
}
void operation_1()
{
printf("请输入生成个数>");
one();
}
void operation_2()
{
printf("请输入生成个数>");
two();
}
void operation_3()
{
printf("请输入生成个数>");
three();
}
void one()
{
int n,a,b,c,d;
time_t t;
srand((unsigned) time(&t));
printf("现在是一年级题目:
");
scanf("%d",&n);
printf("<执行操作:)
");
for (int i=0;i<n;i++)
{
a=rand() % 10;
b=rand() % 10;
c=rand() % 4;
if (c==0)
{
d=a+b;
printf("%d + %d = %d
",a,b,d);
}
else
{
d=a-b;
printf("%d - %d = %d
",a,b,d);
}
}
}
void two()
{
int n,a,b,c;
float d;
time_t t;
srand((unsigned) time(&t));
printf("现在是二年级题目:
");
scanf("%d",&n);
printf("<执行操作:)
");
for (int i=0;i<n;i++)
{
a=rand() % 10;
b=rand() % 10;
c=rand() % 2;
if (c==0)
{
d=a*b;
printf("%d * %d = %g
",a,b,d);
}
else{
while(b==0)
{
b=rand() % 10;
}
d=a/(b*1.0);
printf("%d / %d = %g
",a,b,d);
}
}
}
void three()
{
int n,m,i,a,b,c;
float z;
char fh1[2],fh2[2];
time_t t;
srand((unsigned) time(&t));
printf("现在是三年级题目:
");
scanf("%d",&n);
printf("<执行操作:)
");
char fh[4][6] = {"*","/","+","-"};
for (int i=0; i<n; i++)
{
a=rand() % 100;
b=rand() % 100;
c=rand() % 100;
while (a==0||b==0||c==0)
{
a=rand() % 100;
b=rand() % 100;
c=rand() % 100;
}
strcpy(fh1,fh[rand() % 3]);
strcpy(fh2,fh[rand() % 3]);
if(strcmp(fh1,"*")==0&&strcmp(fh2,"*")==0)
{
z = a * b * c;
printf("%2d %s %2d %s %2d = %g
",a,fh1,b,fh2,c,z);
}
else if(strcmp(fh1,"*")==0&&strcmp(fh2,"/")==0)
{
z = a * b / (c*1.0);
printf("%2d %s %2d %s %2d = %g
",a,fh1,b,fh2,c,z);
}
else if(strcmp(fh1,"*")==0&&strcmp(fh2,"+")==0)
{
z = a * b + c;
printf("%2d %s %2d %s %2d = %g
",a,fh1,b,fh2,c,z);
}
else if(strcmp(fh1,"*")==0&&strcmp(fh2,"-")==0)
{
z = a * b - c;
printf("%2d %s %2d %s %2d = %g
",a,fh1,b,fh2,c,z);
}
else if(strcmp(fh1,"/")==0&&strcmp(fh2,"+")==0)
{
z = a / (b*1.0) + c;
printf("%2d %s %2d %s %2d = %g
",a,fh1,b,fh2,c,z);
}
else if(strcmp(fh1,"/")==0&&strcmp(fh2,"-")==0)
{
z = a / (b*1.0) - c;
printf("%2d %s %2d %s %2d = %g
",a,fh1,b,fh2,c,z);
}
else if(strcmp(fh1,"/")==0&&strcmp(fh2,"/")==0)
{
z = a / (b*1.0) / (c*1.0);
printf("%2d %s %2d %s %2d = %g
",a,fh1,b,fh2,c,z);
}
else if(strcmp(fh1,"+")==0&&strcmp(fh2,"-")==0)
{
z = a + b - c;
printf("%2d %s %2d %s %2d = %g
",a,fh1,b,fh2,c,z);
}
else if(strcmp(fh1,"+")==0&&strcmp(fh2,"+")==0)
{
z = a + b + c;
printf("%2d %s %2d %s %2d = %g
",a,fh1,b,fh2,c,z);
}
else if(strcmp(fh1,"-")==0&&strcmp(fh2,"-")==0)
{
z = a - b - c;
printf("%2d %s %2d %s %2d = %g
",a,fh1,b,fh2,c,z);
}
else if(strcmp(fh1,"/")==0&&strcmp(fh2,"*")==0)
{
z = a / (b*1.0) * c;
printf("%2d %s %2d %s %2d = %g
",a,fh1,b,fh2,c,z);
}
else if(strcmp(fh1,"+")==0&&strcmp(fh2,"/")==0)
{
z = a + b / (c*1.0);
printf("%2d %s %2d %s %2d = %g
",a,fh1,b,fh2,c,z);
}
else if(strcmp(fh1,"+")==0&&strcmp(fh2,"*")==0)
{
z = a + b * c;
printf("%2d %s %2d %s %2d = %g
",a,fh1,b,fh2,c,z);
}
else if(strcmp(fh1,"-")==0&&strcmp(fh2,"/")==0)
{
z = a - b / (c*1.0);
printf("%2d %s %2d %s %2d = %g
",a,fh1,b,fh2,c,z);
}
else if(strcmp(fh1,"-")==0&&strcmp(fh2,"+")==0)
{
z = a - b + c;
printf("%2d %s %2d %s %2d = %g
",a,fh1,b,fh2,c,z);
}
else if(strcmp(fh1,"-")==0&&strcmp(fh2,"*")==0)
{
z = a - b * c;
printf("%2d %s %2d %s %2d = %g
",a,fh1,b,fh2,c,z);
}
}
}
void error()
{
printf("Error!!!
");
printf("错误操作指令, 请重新输入
");
}
2.2.5Gitee上传截图与链接
