第二次实验

#include<stdio.h>
int main(){
char a,b,c,d,e;
a=getchar();
b=getchar();
c=getchar();
d=getchar();
e=getchar();
putchar(a);
putchar(b);
putchar(c);
putchar(d);
putchar(e);
return 0;
}

#include<stdio.h>
int main(){
printf("input the year");
int year,d0ays;
scanf("%d",&year);
if(year%4==0&&year%100!=0||year%400==0){
 printf("year:");
 printf("%d",year);
 printf(",month:2");
 printf(",days:29");
}
else{printf("year:");
  printf("%d",year);
 printf(",month:2");
 printf(",days:28");
}
return 0;
}

#include<stdio.h>
int main(){
double a,b,c;
scanf("%f%f%f",&a,&b,&c);
if((a*a+b*b<c*c)||(b*b+c*c<a*a)||(a*a+c*c<b*b))
{
 printf("不能构成三角形");}
else if((a==b&&a!=c)||(a==c&&a!=b)||(b==c&&a!=b))
{
printf("等腰三角形");}
else if(a==b&&b==c&&a==c)
{
printf("等边三角形");}
else if((a*a+b*b==c*c)||(a*a+c*c==b*b)||(b*b+c*c==a*a))
{
printf("直角三角形");}
else
{
printf("一般三角形");}
return 0;
}

#include<stdio.h>
int main(){
 int a;
double rate,tax,profit;
printf("请输入奖金数");
scanf("%d",&a);
switch(a/500){
case 0:rate=0.00;break;
case 1:rate=0.05;break;
case 2:rate=0.08;break;
case 3:rate=0.08;break;
case 4:rate=0.10;break;
case 5:rate=0.10;break;
case 6:rate=0.10;break;
case 7:rate=0.10;break;
case 8:rate=0.10;break;
case 9:rate=0.10;break;
default:rate=0.15;
}
tax=a*rate;
profit=a-tax;
printf("税率");
printf("%lf ",rate);
printf("应缴税款");
printf("%lf ",tax);
printf("实得奖金数");
printf("%lf",profit);
return 0;
}

#include<stdio.h>
int main(){
 int a;
double rate,tax,profit;
printf("请输入奖金数");
scanf("%d",&a);
if(a<500){
rate=0;}
else if(a<1000){
rate=0.05;}
else if(a<2000){
rate=0.08;}
else if(a<5000){
rate=0.10;}
else{
rate=0.15;}
tax=a*rate;
profit=a-tax;
printf("税率");
printf("%lf ",rate);
printf("应缴税款");
printf("%lf ",tax);
printf("实得奖金数");
printf("%lf",profit);
return 0;
}