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Posted on 2011-10-30 10:35 susu 阅读(491) 评论(0) 编辑 收藏 引用
1
2
3
4#include <stdio.h>
5#define MAX 100
6char exp[MAX];
7
8#if 0
9void tr ans()
10   {
11 char stack[MAX];
12 char str[] = "(56-20)/(4+2)#";
13 char ch;
14 int sum, i, j, t, top = 0;
15  /**//*
16 printf("***************************************\n");
17 printf("* 输入一个求值的表达式，以#结束。只能包含+，-，*，/运算符和正整数 *\n");
18 printf("***************************************\n");
19 printf("算术表达式：");
20
21 i = 0;
22 do
23 {
24 //i++;
25 //scanf("%c ", &str[i]);
26
27 }while (0);
28 //}while (str[i++] != '#' && i != MAX);
29 sum = i;
30 t = 1;
31 i = 1;
32 ch = str[i];
33 i++;*/
34 i = 0;
35 t = 1
36 top = 0
37 while (str[i] != '\0')
38 {
39 ch = str[i];
40 switch (ch)
41 {
42 case '(':
43 top++;
44 stack[top] = ch;
45 break;
46 case ')':
47 while (stack[top] != '(')
48 {
49 exp[t] = stack[top];
50 top--;
51 t++;
52 }
53 top--;
54 break;
55 case '+':
56 case '-':
57 while (top != 0 && stack[top] != '(')
58 {
59 exp[t] = stack[top];
60 top--;
61 t++;
62 }
63 top++;
64 stack[top] = ch;
65 break;
66 case '*':
67 case '/':
68 while (stack[top] == '*' || stack[top] == '/')
69 {
70 exp[t] = stack[top];
71 top--;
72 t++;
73 }
74 top++;
75 stack[top] = ch;
76 break;
77 case ' ':
78 break;
79 default:
80 while (ch >= '0' && ch <= '9')
81 {
82 exp[t] = ch;
83 t++;
84 ch = str[i];
85 i++;
86
87 }
88 i--;
89 exp[t] = '#';
90 t++;
91 }
92 ch = str[i];
93 i++;
94 }
95 while (top != 0)
96 {
97 exp[t] = stack[top];
98 t++;
99 top--;
100 }
101 exp[t] = '#';
102 /**//*
103 printf("\n\t原来表达式：");
104 for (j = 1; j < sum; j++)
105 {
106 printf("%c ", str[j]);
107
108 }*/
109 for (j = 1; j < t; j++)
110 printf("%c ", exp[j]);
111 }
112#endif
113void trans()
114{
115 char stack[MAX];
116 char str[] = "(56-20)/(4+2)";
117 char ch;
118 int s_i;
119 int j;
120 int e_t;
121 int top;
122 s_i = 0;
123 while (str[s_i] != '\0')
124 {
125 printf("str[%d] = %c\n", s_i, str[s_i]);
126 s_i++;
127 }
128 printf("\n");
129 printf("\n");
130 printf("\n");
131
132#if 1
133 s_i = 0;
134 e_t = 0;
135 top = -1;
136 ch = str[s_i];
137 while (str[s_i] != '\0')
138 {
139 ch = str[s_i];
140 s_i++;
141#if 1
142 switch (ch)
143 {
144 case '(':
145 top++;
146 stack[top] = ch;
147 break;
148 case ')':
149 while (stack[top] != '(')
150 {
151 exp[e_t] = stack[top];
152 top--;
153 e_t++;
154 }
155 top--;
156 break;
157 case '+':
158 case '-':
159 while (top != 0 && stack[top] != '(')
160 {
161 exp[e_t] = stack[top];
162 top--;
163 e_t++;
164 }
165 top++;
166 stack[top] = ch;
167 break;
168 case '*':
169 case '/':
170 if ((stack[top] == '*') || (stack[top] == '/'))
171 {
172 exp[e_t] = stack[top];
173 top--;
174 e_t++;
175 }
176 top++;
177 stack[top] = ch;
178 break;
179 case ' ':
180 break;
181 default:
182 while (ch >= '0' && ch <= '9')
183 {
184 exp[e_t] = ch;
185 //printf("exp[%d] = %c\n", e_t, exp[e_t]);
186 e_t++;
187 ch = str[s_i];
188 s_i++;
189 }
190 s_i--;
191 exp[e_t] = '#';
192 e_t++;
193 break;
194 }
195
196#endif
197 }
198 while (top != -1)
199 {
200 exp[e_t] = stack[top];
201 e_t++;
202 top--;
203 }
204 exp[e_t] = '#';
205
206 /**//*
207 printf("\n\t原来表达式：");
208 for (j = 1; j < sum; j++)
209 {
210 printf("%c ", str[j]);
211
212 }*/
213 printf("\n");
214 for (j = 0; j < e_t; j++)
215 {
216 printf("%c",exp[j]);
217 }
218 printf("\n");
219 //printf("exp[%d] = %c\n ",j, exp[j]);
220#endif
221}
222void compvalue()
223{
224 float stack[MAX];
225 float d;
226 char ch;
227 int t = 1;
228 int top = -1;
229 ch = exp[t];
230 //t++; /* 56#20#-4#2#+/ */
231 d = 0;
232 while (ch != '$')
233 {
234 switch (ch)
235 {
236 case '+':
237 stack[top - 1] = stack[top - 1] + stack[top];
238 top--;
239 printf("stack[%d] = %f \n", top, stack[top]);
240 break;
241 case '-':
242 stack[top - 1] = stack[top - 1] - stack[top];
243 top--;
244 printf("stack[%d] = %f \n", top, stack[top]);
245 break;
246 case '*':
247 stack[top - 1] = stack[top - 1] * stack[top];
248 top--;
249 printf("stack[%d] = %f \n", top, stack[top]);
250 break;
251 case '/':
252 if (stack[top] != 0)
253 {
254 stack[top - 1] = stack[top - 1]/stack[top];
255 }
256 else
257 {
258 printf("\n\t除0错误！\n");
259 return;
260 }
261 top--;
262 printf("stack[%d] = %f \n", top, stack[top]);
263 break;
264 case '#':
265 top++;
266 stack[top] = d;
267 printf("stack [%d] = %f \n", top, stack[top]);
268 d = 0;
269 break;
270 default:
271 if (ch >= '0' && ch <= '9')
272 {
273 d = 10 * d + ch - '0';
274 printf("d = %f\n", d);
275 }
276 break;
277 }
278 t++;
279 ch = exp[t];
280 }
281 printf("\n计算结果：stack[%d] = %f\n",top, stack[top]);
282}
283
284void main()
285{
286 //int j;
287 trans();
288 /**//*
289 exp[1] = '5';
290 exp[2] = '6';
291 exp[3] = '#';
292 exp[4] = '2';
293 exp[5] = '0';
294 exp[6] = '#';
295 exp[7] = '-';
296 exp[8] = '4';
297 exp[9] = '#';
298 exp[10] = '3';
299 exp[11] = '#';
300 exp[12] = '+';
301 exp[13] = '/';
302 exp[14] = '$';
303 printf("\n");
304 for (j = 1; j <15; j++)
305 printf("%c", exp[j]);
306 printf("\n");*/
307 //compvalue();
308}
309
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