The---of the data structure The block chain storage representation of the C language implementation string

C language implements the block chain storage representation of the string//Xin Yang # include <stdio.h> #include <stdlib.h> #include <string.h> #define CHUNKSIZE 80# Define TRUE 1 #define FALSE 0 #define OK 1 #define ERROR 0 #define INFEASIBLE-1 #define OVERFLOW-2 Char blank= ' # '; typedef int STATUS; Define the block chain to store the strings of each node of the typedef struct CHUNK{CHAR ch[chunksize];struct Chunk *next;} chunk;//defines the block chain stored by the string typedef struct{chunk *head, *tail;int Curlen;} lstring;   void Initstring (Lstring *t) {(*t). curlen=0;   (*t). Head=null; (*t). Tail=null;   } Status strassign (lstring *t,char *chars) {int i,j,k,l;   Chunk *p,*q;    I=strlen (chars); if (!i| |   STRCHR (Chars,blank)) return ERROR;   (*t). curlen=i;    J=i/chunksize;   if (i%chunksize) j + +;     for (k=0;k<j;k++) {p= (chunk*) malloc (sizeof (Chunk));     if (!p) return ERROR;     if (k==0) (*t). head=q=p;       else {q->next=p;     Q=p;     } for (l=0;l<chunksize&&*chars;l++) * (q->ch+l) =*chars++;       if (!*chars) {(*t). tail=q; Q->next=null;     for (; l<chunksize;l++) * (q->ch+l) =blank; }} return OK;   } Status strcopy (lstring *t,lstring S) {Chunk *h=s.head,*p,*q;   (*t). Curlen=s.curlen;     if (h) {p= (*t). head= (chunk*) malloc (sizeof (Chunk));      *p=*h;     h=h->next;       while (h) {q=p;       p= (chunk*) malloc (sizeof (Chunk));       q->next=p;       *p=*h;     h=h->next;     } p->next=null;     (*t). tail=p;   return OK; } else return ERROR;   } Status Strempty (lstring S) {if (S.curlen) return FALSE; else return TRUE;   } int Strcompare (lstring s,lstring T) {int i=0;   Chunk *ps=s.head,*pt=t.head;    int js=0,jt=0;      while (I<s.curlen&&i<t.curlen) {i++;       while (* (PS-&GT;CH+JS) ==blank) {js++;         if (js==chunksize) {ps=ps->next;       js=0;      }     };       while (* (PT-&GT;CH+JT) ==blank) {jt++;         if (jt==chunksize) {pt=pt->next;   jt=0;    }     };     if (* (PS-&GT;CH+JS)!=* (PT-&GT;CH+JT)) return * (PS-&GT;CH+JS)-* (PT-&GT;CH+JT);       else {js++;         if (js==chunksize) {ps=ps->next;       js=0;       } jt++;         if (jt==chunksize) {pt=pt->next;       jt=0; }}} return S.curlen-t.curlen; } int strlength (lstring S) {return s.curlen;}   Status clearstring (lstring *s) {Chunk *p,*q;   P= (*s). Head;     while (p) {q=p->next;     Free (p);   p=q;   } (*s). Head=null;   (*s). Tail=null;   (*s). curlen=0; return OK;   } Status Concat (lstring *t,lstring s1,lstring S2) {lstring a1,a2;   Initstring (&AMP;A1);   Initstring (&AMP;A2);   Strcopy (&AMP;A1,S1);   Strcopy (&AMP;A2,S2);   (*t). Curlen=s1.curlen+s2.curlen;   (*t). Head=a1.head;   a1.tail->next=a2.head;   (*t). Tail=a2.tail; return OK;   } Status SubString (lstring *sub, lstring s,int pos,int len) {Chunk *p,*q;   int i,k,n,flag=1; if (pos<1| | pos>s.curlen| | len<0| | Len&gT   s.curlen-pos+1) return ERROR;   N=len/chunksize;    if (len%chunksize) n++;   p= (chunk*) malloc (sizeof (Chunk));   (*sub). head=p;     for (i=1;i<n;i++) {q= (chunk*) malloc (sizeof (Chunk));     p->next=q;   p=q;   } p->next=null;   (*sub). tail=p;   (*sub). Curlen=len;   for (i=len%chunksize;i<chunksize;i++) * (p->ch+i) =blank;    Q= (*sub). Head;    i=0;    P=s.head;    n=0;         while (flag) {for (k=0;k<chunksize;k++) if (* (p->ch+k)!=blank) {n++;             if (n>=pos&&n<=pos+len-1) {if (i==chunksize) {q=q->next;           i=0;           } * (Q->ch+i) =* (p->ch+k);           i++;             if (n==pos+len-1) {flag=0;           Break   }}} p=p->next; } return OK;   } int Index (lstring s,lstring t,int pos) {int i,n,m;   Lstring Sub;      if (Pos>=1&&pos<=strlength (s)) {n=strlength (s); M=strlength (T);     I=pos;        while (i<=n-m+1) {SubString (&sub,s,i,m);       if (Strcompare (sub,t)!=0) ++i;     else return i; }} return 0;   } void Zip (lstring *s) {int j,n=0;   Chunk *h= (*s). Head;   Char *q;   Q= (char*) malloc (((*s) curlen+1) *sizeof (char));         while (h) {for (j=0;j<chunksize;j++) if (* (H-&GT;CH+J)!=blank) {* (q+n) =* (H-&GT;CH+J);       n++;   } h=h->next;   } * (Q+n) = 0;    Clearstring (S); Strassign (S,Q);   } Status Strinsert (lstring *s,int pos,lstring T) {int i,j,k;   Chunk *p,*q;   Lstring T; if (pos<1| |   Pos>strlength (*s) +1) return ERROR;    Strcopy (&t,t);    Zip (S);    I= (pos-1)/chunksize;   j= (pos-1)%chunksize;   P= (*s). Head;     if (pos==1) {t.tail->next= (*s). Head;   (*s). Head=t.head;     } else if (j==0) {for (k=1;k<i;k++) p=p->next;      q=p->next;      p->next=t.head;     t.tail->next=q; if (q==null) (*s). Tail=t.Tail      } else {for (k=1;k<=i;k++) p=p->next;      Q= (chunk*) malloc (sizeof (Chunk));      for (i=0;i<j;i++) * (q->ch+i) =blank;       for (i=j;i<chunksize;i++) {* (q->ch+i) =* (p->ch+i);     * (p->ch+i) =blank;     } q->next=p->next;     p->next=t.head;   t.tail->next=q;   } (*s). Curlen+=t.curlen;   Zip (S); return OK;    } Status strdelete (lstring *s,int pos,int len) {int i=1;   Chunk *p= (*s). Head;   int j=0; if (pos<1| | Pos> (*s). curlen-len+1| |   len<0) return ERROR;       while (I<pos) {while (* (P-&GT;CH+J) ==blank) {j + +;         if (j==chunksize) {p=p->next;       j=0;     }} i++;     j + +;       if (j==chunksize) {p=p->next;     j=0;    }   };       while (I<pos+len) {while (* (P-&GT;CH+J) ==blank) {j + +;         if (j==chunksize) {p=p->next;       j=0;      }} * (P->ch+j) =blank;     i++;     j + +; IF (j==chunksize) {p=p->next;     j=0;   }   };   (*s). Curlen-=len; return OK;    } Status Replace (lstring *s,lstring t,lstring V) {int i=1;   if (Strempty (T)) return ERROR;      do {i=index (*s,t,i);       if (i) {strdelete (S,i,strlength (T));       Strinsert (S,I,V);      I+=strlength (V);   }}while (i); return OK;   } void Strprint (lstring T) {int i=0,j;   Chunk *h;   H=t.head; while (I<t.curlen) {for (j=0;j<chunksize;j++) if (* (H-&GT;CH+J)!=blank) {printf ("%c", * (h-&         GT;CH+J));       i++;   } h=h->next; } printf ("\ n");   } void Destroystring () {} int main () {char *s1= "Abcdefghi", *s2= "12345", *s3= "", *s4= "Asd#tr", *s5= "ABCD";   Status K;   int Pos,len;   Lstring T1,t2,t3,t4;   Initstring (&AMP;T1);   Initstring (&AMP;T2);   printf ("=============== delimiter =========================\n"); printf ("String T1 empty after initializing string T1?")   %d (1: Empty 0: NO) string length =%d\n ", Strempty (T1), strlength (t1));   K=strassign (&AMP;T1,S3); if (K==ok)  {printf ("string T1: \ n");   Strprint (t1);   } else printf ("Error \ n");   K=strassign (&AMP;T1,S4);     if (K==ok) {printf ("string T1: \ n");   Strprint (t1);   } else printf ("Error \ n");   K=strassign (&AMP;T1,S1);     if (K==ok) {printf ("string T1: \ n");   Strprint (t1);   } else printf ("Error \ n"); printf ("String T1 empty no?")   %d (1: Empty 0: NO) string length =%d\n ", Strempty (T1), strlength (t1));   Strassign (&AMP;T2,S2);   printf ("string T2: \ n");   Strprint (T2);   Strcopy (&AMP;T3,T1);   printf ("by string T1 copy to get string t3, string t3: \ n");   Strprint (T3);   Initstring (&AMP;T4);   Strassign (&AMP;T4,S5);   printf ("string T4:");   Strprint (T4);   Replace (&AMP;T3,T4,T2);   printf ("=============== delimiter =========================\n");   printf ("T2 replaces string t3 in the T4 string, the string t3 is: \ n");   Strprint (T3);   Clearstring (&AMP;T1);   printf ("=============== delimiter =========================\n"); printf ("After emptying the string T1, the string T1 empty no?")   %d (1: Empty 0: NO) string length =%d\n ", Strempty (T1), strlength (t1));   Concat (&AMP;T1,T2,T3);   printf ("=============== delimiter =========================\n"); printf ("String T1 (=t2+t3) is: \ n"));   Strprint (t1);   Zip (&AMP;T1);   printf ("After removing unnecessary placeholders, string T1: \ n");   Strprint (t1);   Pos=index (t1,t3,1);   printf ("pos=%d\n", POS);   printf ("=============== delimiter =========================\n");   printf ("Insert string T2 before the first POS character in string t1, enter pos: \ n");   scanf ("%d", &pos);   K=strinsert (&AMP;T1,POS,T2);     if (k) {printf ("after inserting the string t2, the string T1 is: \ n");   Strprint (t1); } else printf ("Insert failed!   \ n "); return 0; }

The---of the data structure The block chain storage representation of the C language implementation string