1 #include <stdio.h>
  2 #include <stdlib.h>
  3 #include <string.h>
  4 #define OK 1
  5 #define ERROR 0
  6 #define TRUE 1
  7 #define FALSE 0
  8 #define OVERFLOW -2
  9 typedef int Status;
 10 #define MAXSTRLEN 40 //在255范围内定义最大串长(255为1个字节)
 11 typedef char SString[MAXSTRLEN + 1]; //位置0存放串的长度
 12 /*********************************************************/
 13 Status StrAssign(SString T, char *chars); //字符串赋值
 14 Status StrCopy(SString T, SString S); //字符串拷贝
 15 Status StrEmpty(SString S); //字符串判空
 16 Status StrLength(SString S); //返回字符串长度
 17 Status StrPrint(SString T); //打印字符串
 18 Status ClearString(SString S); //清空字符串
 19 Status Concat(SString T, SString S1, SString S2); //字符串联结
 20 Status Index(SString T, SString S); //索引子串位置
 21 Status StrInsert(SString T, SString S, int pos); //插入子串
 22 Status StrDelete(SString S, int pos, int len); //删除某个位置长度为len的子串
 23 /*自己写的方法,传入两个字符串进行比较,如果完全匹配则相同,不完全匹配则判断是否为子串*/
 24 Status StrCompare(SString T, SString S); //字符串比较
 25 Status StrSubString(SString longStr, SString shortStr); //匹配子串
 26 /*********************************************************/
 27 int main()
 28 {
 29     SString S1, S2, S3, S4, T;
 30     char str[MAXSTRLEN];
 31     int pos, len;
 32     printf("Input S1:");
 33     gets(str); //scanf无法读取到空格
 34     printf("----------------------------------\n");
 35     StrAssign(S1, str);//将输入的str赋值给串S1
 36     printf("str[40]:%s\n", str);
 37     StrPrint(S1);
 38     printf("Length:%d\n", StrLength(S1));
 39     // printf("S1:%s\n", S1 + 1); //跳过S1[0]打印
 40     printf("----------------------------------\n");
 41     StrCopy(S2, S1);
 42     printf("StrCopy... OK.\n");
 43     printf("S2:");
 44     StrPrint(S2);
 45     printf("S2.len:%d\n", StrLength(S2));
 46     printf("----------------------------------\n");
 47     ClearString(S2);
 48     StrEmpty(S2);
 49     printf("----------------------------------\n");
 50     printf("Input S3:");
 51     gets(str);
 52     StrAssign(S3, str);
 53     printf("StrCompare... OK.\n");
 54     StrCompare(S3, S1);
 55     printf("----------------------------------\n");
 56     Concat(S4, S1, S3);
 57     printf("Concat... OK.\n");
 58     printf("S4:");
 59     StrPrint(S4);
 60     printf("Length:%d\n", StrLength(S4));
 61     printf("----------------------------------\n");
 62     printf("Index S4... OK.\n");
 63     printf("Input index str:");
 64     gets(str);
 65     StrAssign(T, str);
 66     Index(T, S4);
 67     printf("----------------------------------\n");
 68     printf("Input Position:");
 69     scanf("%d", &pos);
 70     printf("Insert str to S4... OK.\n");
 71     StrInsert(T, S4, pos);
 72     printf("S4:");
 73     StrPrint(S4);
 74     printf("Length:%d\n", StrLength(S4));
 75     printf("----------------------------------\n");
 76     printf("Input Position and Length:");
 77     scanf("%d %d", &pos, &len);
 78     StrDelete(S4, pos, len);
 79     printf("S4:");
 80     StrPrint(S4);
 81     printf("Length:%d\n", StrLength(S4));
 82     return 0;
 83 }
 84 /* 字符串赋值,当赋值字符串长度超过被赋值字符串时候截断,未超过时先将长度存入T[0],再逐位赋值 */
 85 Status StrAssign(SString T, char *chars)
 86 {
 87     int i;
 88     if (strlen(chars) > MAXSTRLEN)
 89     {
 90         for (i = 1; i <= MAXSTRLEN; ++i)
 91             T[i] = *(chars + i - 1);
 92         T[0] = MAXSTRLEN;
 93     }
 94     else
 95     {
 96         T[0] = strlen(chars); //p.s.此时T[0]存入的是int类型的数据,打印%s时无法显示
 97         for (i = 1; i <= MAXSTRLEN; ++i)
 98             T[i] = *(chars + i - 1);
 99         return OK;
100     }
101 }
102 /* 字符串拷贝,逐个字符拷贝(仅拷贝长度范围内的) */
103 Status StrCopy(SString T, SString S)
104 {
105     int i;
106     //p.s.此处要拷贝长度+1,将S1的\0同时拷贝进去,否则T中没有\0
107     for (i = 1; i <= S[0]; ++i)
108         T[i] = S[i];
109     T[0] = S[0];
110     return OK;
111 }
112 /* 字符串判空,当S[0]==0时为空 */
113 Status StrEmpty(SString S)
114 {
115     if (S[0] == 0)
116     {
117         printf("String is Empty\n");
118         return TRUE;
119     }
120     else
121     {
122         printf("String is not Empty\n");
123         return FALSE;
124     }
125 }
126 /* 返回子串长度 */
127 Status StrLength (SString S)
128 {
129     return S[0];
130 }
131 /* 打印字符串 */
132 Status StrPrint(SString T)
133 {
134     int i;
135     for (i = 1; i <= T[0]; ++i)
136     {
137         printf("%c", T[i]);
138     }
139     printf("\n");
140     return OK;
141 }
142 /* 清空字符串 */
143 Status ClearString(SString S)
144 {
145     S[0] = 0;
146     return OK;
147 }
148 /* 字符串联接,通过T来存储结果,S2连接而成的新串,若未截断则返回TRUE,截断返回FAlSE,注意字符串数组越界问题 */
149 Status Concat(SString T, SString S1, SString S2)
150 {
151     int i;
152     if (S1[0] + S2[0] <= MAXSTRLEN)
153     {
154         for (i = 1; i <= S1[0]; ++i)
155             T[i] = S1[i];
156         for (i = 1; i <= S2[0]; ++i)
157             T[i + S1[0]] = S2[i];
158         T[0] = S1[0] + S2[0];
159         return TRUE;
160     }
161     else //先存完S1中的,再存S2中的内容,条件是不能越界
162     {
163         for (i = 1; i <= S1[0] && i <= MAXSTRLEN - 1; ++i)
164             T[i] = S1[i];
165         for (i = 1; i <= MAXSTRLEN - S1[0]; ++i)
166             T[i + S1[0]] = S2[i];
167         T[0] = MAXSTRLEN;
168         return FALSE;
169     }
170 }
171 /* 索引子串 */
172 Status Index(SString T, SString S)
173 {
174     int i = 1, j = 1;
175     while(j <= T[0] && i <= S[0])
176     {
177         if (T[j] == S[i])
178         {
179             ++i;
180             ++j;
181         }
182         else
183         {
184             i = i - j + 2;
185             j = 1;
186         }
187     }
188     if (j > T[0])
189     {
190         printf("Position:%d\n", i - j + 1);
191         return OK;
192     }
193     else
194     {
195         printf("substring is not exist\n");
196         return ERROR;
197     }
198 }
199 /* 在位置pos处插入子串T */
200 Status StrInsert(SString T, SString S, int pos)
201 {
202     int i;
203     if (pos > S[0])
204         pos = S[0] + 1;
205     if (S[0] + T[0] <= MAXSTRLEN)
206     {
207         for (i = S[0] + T[0]; i >= pos + T[0]; --i)
208             S[i] = S[i - T[0]];
209         for (i = 1; i <= T[0]; ++i)
210             S[pos + i - 1] = T[i];
211         S[0] = S[0] + T[0];
212         return OK;
213     }
214     else
215     {
216         for (i = MAXSTRLEN; i >= pos + T[0]; --i)
217             S[i] = S[i - T[0]];
218         for (i = 1; i <= T[0]; ++i)
219             S[pos + i - 1] = T[i];
220         S[0] = MAXSTRLEN;
221         return ERROR;
222     }
223 }
224 Status StrDelete(SString S, int pos, int len)
225 {
226     int i;
227     if (pos > S[0])
228         return ERROR;
229     else if (pos + len > S[0])
230         len = S[0] - pos + 1;
231     for (i = pos + len; i <= S[0]; ++i)
232         S[i - len] = S[i];
233     S[0] -= len;
234 }
235 /* 字符串比较。比较字符串是否完全相同,如果不同则判断子串所在的位置 */
236 Status StrCompare(SString T, SString S)
237 {
238     int i, j;
239     /* 当两个字符串长度相同时,逐个判断字符是否相同,不相同则退出,相同则继续比较 */
240     if (T[0] == S[0])
241     {
242         for (i = 1; i <= S[0]; ++i)
243         {
244             if (T[i] != S[i])
245             {
246                 printf("A.len==B.len , A!=B \n");
247                 return ERROR;
248             }
249         }
250         printf("A == B\n");
251         return OK;
252     }
253     else if(T[0] < S[0])
254         StrSubString(T, S);
255     else if(T[0] > S[0])
256         StrSubString(S, T);
257 }
258 /* 判断A是否是B的子串。逐个遍历长字符串,当短字符串首字符与长字符串字符相同时,短字符串与长字符串逐个比较,中途有不匹配的情况则重新开始比较,长字符串继续遍历，如果短字符串比对完并且最后一个字符也相同时则是子串 */
259 Status StrSubString(SString shortStr, SString longStr)
260 {
261     int i, j = 1;
262     for (i = 1; i <= longStr[0]; ++i)
263     {
264         if (shortStr[1] == longStr[i])
265         {
266             for (j = 1; j <= shortStr[0] ; ++j)
267             {
268                 if (j == shortStr[0] && shortStr[j] == longStr[j + i - 1])
269                 {
270                     printf("A is substring of B.Location is:%d\n", i);
271                     return OK;
272                 }
273                 if (shortStr[j] != longStr[j + i - 1])
274                     break;
275             }
276         }
277     }
278     printf("A not substring of B\n");
279     return ERROR;
280 }