数据结构算法C语言实现（十四）--- 4.1&4.2串的类型定义、表示及实现

　　一.简述

　　【暂无】

　　二.头文件

 //4_2_part1.h
 /**
 author:zhaoyu
 */
 //2016-6-10
 //----串的定长顺序存储表示----
 #include "head.h"
 #define MAXSTRLEN 255//用户可以在255以内定义最大串长
 //这语法还不是很熟悉
 typedef unsigned char SString[MAXSTRLEN+];//0 号单元存放串的长度
 int StrLength(SString T)
 {
     for (int i = ; i <= MAXSTRLEN; ++i)
     {
         if ('\0' == T[i])
         {
             return i-;
         }
     }
     return MAXSTRLEN;
 }

 /**
 algorithm 4.2
 */
 Status Concat(SString &T, SString S1, SString S2)
 {
     //用 T 返回由 S1 和 S2 连接而成的新串。
     //若未截断，则返回 TRUE，否则返回 FALSE
     Status uncut;
     if (S1[] + S2[] < MAXSTRLEN)
     {//未截断
         int i = ;
         for (i = ; i <= S1[]; ++i)
         {
             T[i] = S1[i];
         }
         for (i = ; i <= S2[]; ++i)
         {
             T[S1[]+i] = S2[i];
         }
         T[] = S1[] + S2[];
         uncut = TRUE;
     }
     else if (S1[] < MAXSTRLEN)
     {
         int i = ;
         for (i = ; i <= S1[]; i++)
         {
             T[i] = S1[i];
         }
         for (i = S1[]+; i <= MAXSTRLEN; i++)
         {
             T[i] = S2[i-S1[]];
         }
         T[] = MAXSTRLEN;
         uncut = FALSE;
     }
     else
     {
         for (int i = ; i <= MAXSTRLEN; i++)
         {
             T[i] = S1[i];
         }
         T[] = S1[] = MAXSTRLEN;
         uncut = FALSE;
     }
     return uncut;
 }
 /**
 algorithm 4.3
 */
 Status SubString(SString &Sub, SString S, int pos, int len)
 {
     //用 Sub 返回串 S 的第 pos 个字符起长度为 len 的字串
     //其中， 1<= pos <<= SreLength(S) 且 0 <= len <= StrLength(S)-pos+1
     if (pos <  || pos > S[] || len <  || len > S[]-pos+)
     {
         return ERROR;
     }
     for (int i = ; i <= len; i++)
     {
         Sub[i] = S[i+pos-];
     }
     Sub[] = len;
     return OK;
 }
 void PrintSString(SString T)
 {
     //if(T[])
     for (int i = ; i <= T[]; ++i)
     {
         printf("%c", *(T+i));
     }
     printf("\n");
 }

 4_2_part1.h

4_2_part1.h

 //4_2_part2.h
 /**
 author:zhaoyu
 */
 //2016-6-12
 #include "head.h"
 #include <cstdlib>
 #include <cstring>
 //----串的对分配存储表示----
 typedef struct {
     char *ch;//
     int length;
 }HString;

 Status StrInsert(HString &S, int pos, HString T)
 {//1<= pos <= StrLength(S)+1
 //在串的第 pos 个字符之前插入串 T
     if ( < pos || pos > S.length + )
     {
         printf("Illegal pos\n");
         return ERROR;
     }
     if (T.length){//T 非空，则重新分配空间，插入 T
         if (!(S.ch = (char *)realloc(S.ch, (S.length +
          T.length)*sizeof(char))));
         {
             exit(OVERFLOW);
         }
         for (int i = S.length-; i >= pos-; i--)
         {//为插入 T 为腾出位置
             S.ch[i+T.length] = S.ch[i];
         }
         for (int i = pos-; i <= pos+T.length-; i++)
         {//插入 T
             S.ch[i] = T.ch[i];
         }
         S.length += T.length;
     }
     return OK;
 }
 //page 76-77
 //----基本操作的算法描述----
 Status StrAssign(HString &T, char *chars)
 {//生成一个其值等于串常量 chars的串 T
     if (T.ch)
     {
         T.ch = NULL;
     }
     int L;
     char *c;;
     for (L = , c = chars; *c!='\0'; ++L, ++c);//求 chars 的长度 L
     if(!L)
     {
         T.ch = NULL;
         T.length = ;
     }
     else
     {
         if (!(T.ch = (char *)malloc(L*sizeof(char))))
         {
             exit(OVERFLOW);
         }
         for (int i = ; i < L; ++i)
         {
             T.ch[i] = chars[i];
         }
         T.length = L;
     }
     return OK;
 }
 int StrLength(HString S)
 {//返回 S 的元素个数， 称为串的长度
     return S.length;
 }
 int StrCompare(HString S, HString T)
 {//若 S >|=|< T，则返回 >|=|< 0
     for (int i = ; i < S.length && i < T.length; i++)
     {
         if (T.ch[i] != S.ch[i])
         {
             return S.ch[i] - T.ch[i];
         }
     }
     return S.length - T.length;
 }
 Status ClearString(HString &S)
 {
     //将 S 清空为空串
     if (S.ch)
     {
         free(S.ch);
         S.ch = NULL;
     }
     S.length = ;
     return OK;
 }
 Status Concat(HString &T, HString S1, HString S2)
 {
     if (T.ch)
     {//释放旧空间
         free(T.ch);
     }
     if (!(T.ch = (char *)malloc((S1.length+S2.length)*sizeof(char))))
     {
         exit(OVERFLOW);
     }
     for (int i = ; i < S1.length; ++i)
     {
         T.ch[i] = S1.ch[i];
     }
     for (int i = ; i < S2.length; ++i)
     {
         T.ch[i+S1.length] = S2.ch[i];
     }
     T.length = S1.length + S2.length;
     return OK;
 }
 Status SubString(HString &Sub, HString S, int pos, int len)
 {
     //用 Sub 返回串 S 的第 pos 个字符起长度为 len 的子串
     //其中，其中， 1<= pos <<= SreLength(S) 且 0 <= len <= StrLength(S)-pos+1
     if (pos <  || pos > S.length || len <  || len > S.length-pos+)
     {
         return ERROR;
     }
     if (Sub.ch)
     {
         free(Sub.ch);
     }
     if (!len)
     {//空子串
         Sub.ch = NULL;
         Sub.length = ;
     }
     else
     {
         Sub.ch = (char *)malloc(len*sizeof(char));
         for (int i = ; i < len; ++i)
         {
             Sub.ch[i] = S.ch[pos+i-];
         }
         Sub.length = len;
     }
     return OK;
 }
 void PrintHString(HString S)
 {
     for (int i = ; i < S.length; ++i)
     {
         printf("%c", S.ch[i]);
     }
     printf("\n");
 }

4_2_part2.h

　　三.CPP文件

 #include "4_2_part1.h"
 int main(int argc, char const *argv[])
 {
     SString S1;
     SString S2;
     SString T;
     scanf("%s", S1+);
     *S1 = StrLength(S1);
     scanf("%s", S2+);
     *S2 = StrLength(S2);
     Concat(T, S1, S2);
     PrintSString(T);
     int pos = , len = ;
     SubString(T, S1, pos, len);
     PrintSString(T);
     return ;
 }

4_2_part1.cpp

 #include "4_2_part2.h"
 int main(int argc, char const *argv[])
 {
     char S[];
     HString T = {NULL, };
     HString S1 = {NULL, };
     HString S2 = {NULL, };
     scanf("%s", S);
     StrAssign(S1, S);
     printf("S1:\t");
     PrintHString(S1);
     printf("StrLength\t%d\n", StrLength(S1));
     scanf("%s", S);
     StrAssign(S2, S);
     printf("S2\t");
     PrintHString(S2);
     printf("StrLength\t%d\n", StrLength(S1));
     printf("Compare S1 vs S2\t%d\n", StrCompare(S1, S2));
     Concat(T, S1, S2);
     printf("T = S1 + S2\t");
     PrintHString(T);
     SubString(S1, T, , );
     printf("Sub :T[2]-T[4]\t");
     PrintHString(S1);
     return ;
 }

4_2_part2.cpp

　　四.测试

　　连接

　　

　　求子串

　　

　　比较串