四则运算作业

 1  //1302011方春阳 计科13-1 
 2  #include<stdio.h>
 3  #include <time.h>
 4  #include<stdlib.h>
 5 
 6  #define N 45
 7  main()
 8  {
 9      int a,b,k,i,n;
10      float c,d;
11      srand(time(NULL));
12      do{
13       printf("\n请输入数字类型(1.整数 2.小数) -1为退出程序: ");
14       scanf("%d",&n);
15  
16       switch(n)
17       {
18        case 1:
19           {
20           for(i=0;i<N;i++)
21           {
22             a=rand()%100+1;
23             b=rand()%100+1;
24             k=rand()%4+1;
25            printf("%d",a);
26            switch(k)
27           {
28             case 1:printf("+");break;
29             case 2:printf("-");break;
30             case 3:printf("*");break;
31            case 4:printf("/");break;
32            }
33             printf("%d=\t\t",b);
34           }
35            break;
36           }
37         break;
38         case 2:
39           {
40            for(i=0;i<N;i++)
41            {
42             c=rand()*0.001+1;
43            d=rand()*0.001+1;
44             k=rand()%4+1;
45             printf("%0.2f",c);
46             switch(k)
47             {
48              case 1:printf("+");break;
49               case 2:printf("-");break;
50               case 3:printf("*");break;
51               case 4:printf("/");break;
52             }
53             printf("%0.2f=\t",d);
54             }
55            break;
56           }
57            break;
58            }
59          }
60         while(n!=-1);
61 }
62 //2016.03.16