1 /************************************************************************/
2 /* 简单的计算器实现 */
3 /************************************************************************/
4
5
6 #include <stdio.h>
7 #include <ctype.h>
8
9 void Play(void);
10 void GetS(void);
11 float Get_one(void);
12 float Get_two(void);
13
14 int main()
15 {
16 int ch;
17 float one;
18 float two;
19
20 Play();
21 while ((ch = getchar()) != 'q')
22 {
23 switch(ch)
24 {
25 case 'a':
26 one = Get_one();
27 two = Get_two();
28 printf("%.2f + %.2f = %.2f\n", one, two, one + two);
29 break;
30 case 's':
31 one = Get_one();
32 two = Get_two();
33 printf("%.2f - %.2f = %.2f\n", one, two, one - two);
34 break;
35 case 'm':
36 one = Get_one();
37 two = Get_two();
38 printf("%.2f * %.2f = %.2f\n", one, two, one * two);
39 break;
40 case 'd':
41 one = Get_one();
42 two = Get_two();
43 printf("%.2f / %.2f = %.2f\n", one, two, one / two);
44 break;
45
46 }
47 while (getchar() !='\n')
48 {
49 continue;
50 }
51 Play();
52 }
53 printf("Good Bye!");
54
55 getch();
56
57 return 0;
58 }
59
60 void Play(void)
61 {
62 printf("Enter the Operation of your choice:\n");
63 printf("a. add\t\ts. subtract\n");
64 printf("m. multiply\td. divide\n");
65 printf("q. quit\n");
66 }
67
68 void GetS(void)
69 {
70 int ch;
71
72 while ((ch = getchar()) != '\n')
73 {
74 putchar(ch);
75 }
76 }
77
78 float Get_one(void)
79 {
80 float one;
81
82 while (1)
83 {
84 printf("Enter First number:");
85 if (scanf("%f", &one) && one != 0)
86 {
87 return one;
88 }
89 GetS();
90 printf(" is not an number\n");
91
92 }
93
94 }
95
96 float Get_two(void)
97 {
98 float two;
99 while (1)
100 {
101 printf("Enter second number:");
102 if (scanf("%f", &two) && two != 0)
103 {
104 return two;
105 }
106 GetS();
107 printf(" is not an number\n");
108
109 }
110 }
