第二次作业

 1 int main()
 2 {
 3     int grade;
 4     printf("请输入成绩");
 5     scanf("%d",&grade);
 6     if(grade<0&&grade>100)
 7     {
 8         printf("输入错误");
 9     }
10     if(grade>=90)
11     {printf("A");
12      } 
13     else if(grade>=80&&grade<=89)
14     {printf("B");
15     }
16     else if(grade>70&&grade<=79)
17     {printf("C");
18     }
19     else if(grade>=60&&grade<=69)
20     {printf("D");
21     }
22     else if(grade<60&&grade>=0)
23     {printf("E");
24     }
25     return 0;
26     }

 1 #include<stdio.h>
 2 int main()
 3 {
 4     int a,b,c,d,e;
 5     printf("输入一个五位数");
 6     scanf("%d",&e);
 7     a=e/10000;
 8     b=e%10000/1000;
 9     c=e%100/10;
10     d=e%10;
11      if(a==d&&b==c) 
12     {
13     printf("这是一个回文数\n");
14     }
15     else
16     {
17      printf("这不是回文数\n");
18      } 
19      return 0;
20  }

 1 #include<stdio.h>
 2 int main()
 3 {    
 4     int grade;
 5     printf("ÇëÊäÈë³É¼¨");
 6     scanf("%d",&grade);
 7     switch(grade/10)
 8     {
 9     case 9:printf("A\n");break;
10     case 8:printf("B\n");break;
11     case 7:printf("C\n");break;
12     case 6:printf("D\n");break;
13     case 5:
14     case 4:
15     case 3:
16     case 2:
17     case 1:
18     case 0:printf("E\n");break;
19     default:printf("error");
20     }
21         return 0;
22  }

 1 #include<stdio.h>
 2 int main()
 3 {
 4     int a,b,c,d,e,f,g;
 5     printf("ÊäÈëÊý¾Ý");    
 6     scanf("%d",&a) ;
 7      if(a>=100000||a<0)
 8      {
 9       printf("error\n");
10      }
11      else
12      {
13         if(a>=10000&&a<99999)
14      {
15        b=a/10000;
16        c=a/1000%10;
17        d=a/100%10;
18        e=a/10%10;
19        f=a%10;
20        g=f*10000+e*1000+d*100+c*10+b;
21        printf("¸ÃÊýÊÇÎåλÊý£¬ÄæÐòΪ%d\n",g) ;
22       }
23       else if(a>=1000&&a<9999)
24       {
25        b=a/1000;
26        c=a/100%10;
27        d=a/10%10;
28        e=a/10;
29        f=e*1000+d*100+c*10+b;
30        printf("¸ÃÊýÊÇËÄλÊý£¬ÄæÐòΪ%d\n",f);
31       }
32       else if(a>=100&&a<999)
33       {
34        b=a/100;
35        c=a/10%10;
36        d=a%10;
37        e=d*100+c*10+b;
38        printf("¸ÃÊýÊÇÈýλÊý£¬ÄæÐòΪ%d\n",e);
39       }
40       else if(a>=10&&a<99)
41       {
42        b=a/10;
43        c=a%10;
44        d=c*10+b;
45        printf("¸ÃÊýÊǶþλÊý£¬ÄæÐòΪ%d\n",d);
46       }
47       else
48       {
49        printf("¸ÃÊýÊÇһλÊý£¬ÄæÐòΪ%d\n",a);
50       }
51      }
52      return 0;
53 }

1、注意判断语句的对应

2、注意计算正确

3、注意输入数值的合法性

4、注意实型常量和整形常量的转换--结论

原文地址:https://www.cnblogs.com/1998li/p/5964248.html