1.先告诉等级，再显示成绩
设计思路：
注意;break使用。
代码：
#include
int main()
{
char grade;
scanf("%c",&grade);
printf("Your grade:");
switch(grade)
{
case 'A' :printf("85~100\n");break;
case 'B' :printf("70~84\n");break;
case 'C' :printf("60~69\n");break;
case 'D' :printf("<60\n");break;
default: printf("enter error data!\n");
}
return 0;
}
结果展示：
2.先告诉成绩，再显示等级
先告诉成绩，显示等级，需要在switch的表达式里进行计算-写出判断表达式，为了缩到1,2,3，则强制转换(（int）(score/10))
代码：
#include
int main()
{
float score;
char grade;
printf("请输入学生的成绩：");
scanf("%f",&score);
while(score>100||score<0)
{
printf("\n输入有误，请重输");
scanf("%f",&score);
}
switch((int)(score/10))
{
case 10:
case 9:grade='A';break;
case 8:grade='B';break;
case 7:grade='C';break;
case 6:grade='D';break;
case 5:
case 4:
case 3:
case 2:
case 1:
case 0:grade='E';
}
printf("成绩是%5.lf%,相应的等级是%c\n",score,grade);
return 0;
}
结果展示：
3.
代码
#include
int main()
{
int num,indiv,ten,hundred,thousand,ten_thousand,place;
printf("请输入一个整数(0-99999)：");
scanf("%d",&num);
if(num>9999)
place = 5;
else if(num>999)
place=4;
else if(num>99)
place=3;
else if(num>9)
place=2;
else place=1;
printf("位数：%d\n",place);
printf("每位数字为：");
ten_thousand=num/10000;
thousand=(int)(num-ten_thousand*10000)/1000;
hundred=(int)(num-ten_thousand*10000-thousand*1000)/100;
ten=(int)(num-ten_thousand*10000-thousand*1000-hundred*100)/10;
indiv=(int)(num-ten_thousand*10000-thousand*1000-hundred*100-ten*10);
switch(place)
{
case 5:printf("%d,%d,%d,%d,%d",ten_thousand,thousand,hundred,ten,indiv);
printf("\n反序数字为：");
printf("%d%d%d%d%d\n",indiv,ten,hundred,thousand,ten_thousand);
break;
case 4:printf("%d,%d,%d,%d",thousand,hundred,ten,indiv);
printf("\n反序数字为：");
printf("%d%d%d%d\n",indiv,ten,hundred,thousand);
break;
case 3:printf("%d,%d,%d",hundred,ten,indiv);
printf("\n反序数字为：");
printf("%d%d%d\n",indiv,ten,hundred);
break;
case 2:printf("%d,%d",ten,indiv);
printf("\n反序数字为：");
printf("%d%d\n",indiv,ten);
break;
case 1:printf("%d",indiv);
printf("\n反序数字为：");
printf("%d\n",indiv);
break;
}
return 0;
}
结果展示：
4.
5.
6.