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()
{
 int year;
 scanf("%d", &year);
 if((year%100 != 0 && year%4 == 0) || year%400 == 0){
  printf("year:%d, day:29\n",year);
 } else  {
  printf("year:%d,day:28\n",year);
 }
 return 0;
}

#include<stdio.h>
int main()
{
 double a,b,c;
 scanf("%lf%lf%lf",&a,&b,&c);
 if((a + b)<=c||(a+c)<=b||(b+c)<=a){
  printf("无法构成三角形");
 } else if (a==b&&b==c){
  printf("构成等边三角形");
 } else if(a==b||a==c||b==c){
  printf("构成等腰三角形");
 } else if((a*a+b*b)==c*c||(a*a+c*c)==b*b||(b*b+c*c)==a*a){
  printf("构成直角三角形");
 } else {
  printf("构成一般三角形");
 } return 0;
}

 

 

 

 

 

 

 

#include<stdio.h>

#include<math.h>

int main(){  

int a;

 double r[5];

 r[0]=0.00;

 r[1]=0.05;

 r[2]=0.08;

 r[3]=0.10;

 r[4]=0.15;

 scanf("%d",&a);

 if(a<500){   printf("a=%d,rate=%lf,tax=%lf,profit=%lf\n",a,r[0],a*r[0],a-a*r[0]);  }

 if(a>=500&&a<1000){   printf("a=%d,rate=%lf,tax=%lf,profit=%lf\n",a,r[1],a*r[1],a-a*r[1]);  }

 if(a>=1000&&a<2000){   printf("a=%d,rate=%lf,tax=%lf,profit=%lf\n",a,r[2],a*r[2],a-a*r[2]);  }

 if(a>=2000&&a<5000){   printf("a=%d,rate=%lf,tax=%lf,profit=%lf\n",a,r[3],a*r[3],a-a*r[3]);  }

 if(a>=5000){   printf("a=%d,rate=%lf,tax=%lf,profit=%lf\n",a,r[4],a*r[4],a-a*r[4]);  }

 return 0; }