作业6

1.编写程序判断n是正数还是负数。

#include<stdio.h>

main(){

         int n;

         printf("输入一个整数:\n");

         scanf("%d",&n);

         if(n>0)

                  printf("%d是正数!\n",n);

         else if(n==0)

                  printf("%d既不是正数，也不是负数!\n",n);

         else

                  printf("%d是负数!\n",n);

}

 

 

 

 2.使用条件运算符，找出a，b，c，d四个数中最大的数。

#include<stdio.h>

main(){

         double a,b,c,d,m1,m2,max;

         printf("输入四个数字:\n");

         scanf("%lf%lf%lf%lf",&a,&b,&c,&d);

         m1=a>b?a:b;

         m2=c>d?c:d;

         max=m1>m2?m1:m2;

         printf("Max=%f\n",max);

}

 

 

 

 3.已知商场进行促销活动，对于消费的价格有折扣活动，即消费1000元，打9折；消费2000元打8.5折；消费3000元，打7折；消费5000元，打6折，编写程序代码求出消费者实际花费价格。

#include<stdio.h>

main(){

         float price;

         printf("输入购买商品价格:\n");

         scanf("%f",&price);

         if(price>=5000)

                  printf("实际需要支付:%.2f元\n",price*0.6);

         else if(price>=3000)

                  printf("实际需要支付:%.2f元\n",price*0.7);

         else if(price>=2000)

                  printf("实际需要支付:%.2f元\n",price*0.85);

         else if(price>=1000)

                  printf("实际需要支付:%.2f元\n",price*0.9);

         else

                  printf("实际需要支付:%.2f元\n",price);

}

 

 

 

 

 4.输入年份，月份，判断该月有多少天。

#include<stdio.h>

main(){

         int a,b,c;

         printf("请输入年份月份,并用逗号隔开:");

         scanf("%d,%d",&a,&b);

                  if(a%4==0&&a%100!=0||a%400==0){

                          if(b==1||b==3||b==5||b==7||b==8||b==10||b==12){

                                   c=31;

                          }else if(b==4||b==6||b==9||b==11){

                                            c=30;

                                   }else{

                                            c=29;

                                   }

                          }else{

                                   if(b==1||b==3||b==5||b==7||b==8||b==10||b==12){

                                            c=31;

                                   }else if(b==4||b==6||b==9||b==11){

                                            c=30;

                                   }else{

                                            c=28;

                                   }

                          }

                          printf("%d月有%d天\n",b,c);

                  }

 

 

 

 

 5.输入三条边，判断是否可以构成三角形（任意两边之和大于第三边）

#include<stdio.h>

main(){

         int a,b,c;

         printf("请依次输入三角形的三条边并以逗号隔开:");

                  scanf("%d,%d,%d",&a,&b,&c);

         if(a+b>c&&a+c>b&&b+c>a)

         {

                  printf("%d,%d,%d这3条边能组成三角形.",a,b,c);

         }

         else

                  printf("%d,%d,%d这3条边不能组成三角形.",a,b,c);

}