串的基本操作

#include<iostream>using namespace std;#define ok 1#define error 0typedef int Status;//------------------串的堆分配存储表示-------------------typedef struct{char *ch;//若是非空串，则按串长分配存储区，否则ch为NULLint length;//串长度}HString;//------------------基本操作的函数原型说明---------------class StringOperation{public://生成一个其值等于串常量chars的串TStatus StrAssign(HString &T,char *chars,int length);//返回S的元素个数，称为串的长度int StrLength(HString S);//若S>T,则返回值>0;若S=T，则返回值=0;若S<T,则返回值<0int StrCompare(HString S,HString T);//将S清为空串，并释放S所占空间Status ClearString(HString &S);//用T返回由S1和S2连接而成的新串Status Concat(HString &T,HString S1,HString S2);//1<=pos<=StrLength(S)且0<=len<=StrLength(S)-pos+1//返回串S的第pos个字符起长度为len Status SubString(HString &Sub,HString S,int pos,int len);//若主串S中存在和串T值相同的子串，则返回它在主串中S中第pos个字符之后第一次出现的位置，否则函数值为0int Index(HString S,HString T,int pos);//采用KMP算法进行模式匹配int Index_KMP(HString S,HString T,int pos);//若串S，T，V存在，且串T是非空串，用V替换主串S中出现的所有与T相等的不重叠的子串Status Replace(HString &S,HString T,HString V);//若串S存在，则输出串S总的字符Status StrOutput(HString S);//若串S为空串则返回true，否则返回falseStatus StrEmpty(HString S);//在串S的第pos个字符之前插入串TStatus StrInsert(HString &S,int pos,HString T);//串S存在，由串S复制得到串TStatus StrCopy(HString &T,HString S);//从串S中删除第pos个字符起长度为len的子串Status StrDelete(HString &S,int pos,int len);//销毁串SStatus StrDestroy(HString &S);};//StringOperationStatus StringOperation::StrAssign(HString &T,char *chars,int length){int i=0;char *c=chars;if(T.ch)//T中存有字符串,则释放T原有空间{delete T.ch;T.ch=NULL;T.length=0;}//ifif(0==length)//chars为空串{T.ch=NULL;T.length=0;}//ifelse{T.ch=new char[length];if(!T.ch){cout<<"内存分配失败"<<endl;exit(-1);}//iffor(int k=0;k<length;k++)*(T.ch+k)=*(chars+k);T.length=length;}//elsereturn ok;}//StrAssignint StringOperation::StrLength(HString S){return S.length;}//Strlength int StringOperation::StrCompare(HString S,HString T){for(int i=0;i<S.length&&i<T.length;i++){if(S.ch[i]!=T.ch[i])return S.ch[i]-T.ch[i];}//forreturn S.length-T.length;}//StrCompareint StringOperation::ClearString(HString &S){if(S.ch){delete S.ch;S.ch=NULL;}//ifS.length=0;return ok;}//ClearString Status StringOperation::Concat(HString &T,HString S1,HString S2){if(T.ch){delete T.ch;T.ch=NULL;}//ifT.ch=new char[S1.length+S2.length];if(!T.ch){cout<<"内存分配不成功"<<endl;exit(-1);}//iffor(int i=0;i<S1.length;i++)T.ch[i]=S1.ch[i];for(int i=S1.length;i<S1.length+S2.length;i++)T.ch[i]=S2.ch[i-S1.length];T.length=S1.length+S2.length;return ok;}//ConcatStatus StringOperation::SubString(HString &Sub,HString S,int pos,int len){if(pos<1||pos>S.length||len<0||len>S.length-pos+1)return error;if(Sub.ch){delete Sub.ch;Sub.ch=NULL;}//ifif(0==len){Sub.ch=NULL;Sub.length=0;}//ifelse{Sub.ch=new char[len];for(int i=0;i<len;i++)Sub.ch[i]=S.ch[pos-1+i];Sub.length=len;}//elsereturn ok;}//SubStringint StringOperation::Index(HString S,HString T,int pos){int i=pos,j=0,k=1;if(pos<1||pos>S.length)return error;while(i<S.length&&j<T.length){if(S.ch[i]==T.ch[j]){i++;j++;}//ifelse//从pos下一个位置重新匹配{i=pos+k;k++;j=0;}//else}//whileif(j>=T.length)//匹配成功return i-j+1;elsereturn 0;}//Indexvoid get_next(HString T,int str[]){int i=1,j=0;str[1]=0;while(i<T.length){if(0==j||T.ch[i]==T.ch[j]){i++;j++;str[i]=j;}//ifelsej=str[j];}//while}//get_nextint StringOperation::Index_KMP(HString S,HString T,int pos){int next[20];get_next( T, next);if(pos<1||pos>S.length){cout<<"pos is error"<<endl;exit(-1);}//ifint i=pos, j=1;while(i<=S.length&&j<=T.length){if(0==j||S.ch[i-1]==T.ch[j-1]){i++;j++;}//ifelse j=next[j];}//whileif(j>=T.length)return i-T.length;elsereturn 0;}//Index_KMPStatus StringOperation::Replace(HString &S,HString T,HString V){int i=1,locate=0;HString Sub,TT1,TT2;Sub.ch=NULL;Sub.length=0;TT1.ch=0;TT1.length=0;TT2.ch=0;TT2.length=0;while(i<=S.length-T.length+1){locate=Index(S,T,i);if(locate){if(T.length!=S.length-locate+1)//与T相等的串不在串S的末尾SubString(Sub,S,locate+T.length,S.length-(locate+T.length)+1);//将Pos后除T的剩余串复制到Sub中elseClearString(Sub);Concat(TT1,V,Sub);if(1<locate)//与T相等的串不在S的开头SubString(Sub,S,1,locate-1);//将串S中pos位置前的字符复制到Sub中elseClearString(Sub);Concat(TT2,Sub,TT1);StrAssign(S,TT2.ch,TT2.length);i=locate+V.length-1;}//if}//whileStrDestroy(Sub);StrDestroy(TT1);StrDestroy(TT2);return ok;}//ReplaceStatus StringOperation::StrOutput(HString S){int i=0;while(i<S.length){cout<<S.ch[i];i++;}//whilereturn ok;}//HStringStatus StringOperation::StrEmpty(HString S){if(S.length)return false;elsereturn true;}//StrEmptyStatus StringOperation::StrInsert(HString &S,int pos,HString T){HString Sub,TT1,TT2;Sub.ch=NULL;TT1.ch=NULL;TT2.ch=NULL;Sub.length=0;TT1.length=0;TT2.length=0;if(pos>S.length||pos<1){cout<<"pos is error "<<endl;exit(-1);}//ifif(1==pos){Concat(TT1,T,S);StrAssign(S,TT1.ch,TT1.length);}//ifelse{SubString(Sub,S,pos,S.length-pos+1);Concat(TT1,T,Sub);SubString(Sub,S,1,pos-1);Concat(TT2,Sub,TT1);StrAssign(S,TT2.ch,TT2.length);}//elseStrDestroy(Sub);StrDestroy(TT1);StrDestroy(TT2);return ok;}//StrInsertStatus StringOperation::StrCopy(HString &T,HString S){StrAssign(T,S.ch,S.length);return ok;}//StrCopyStatus StringOperation::StrDelete(HString &S,int pos,int len){HString  Sub1,Sub2;Sub1.ch=NULL;Sub1.length=0;Sub2.ch=NULL;Sub2.length=0;if(pos<1||pos>S.length-len+1){cout<<"pos is error"<<endl;exit(-1);}//ifSubString(Sub1,S,pos+len,S.length-pos-len+1);SubString(Sub2,S,1,pos-1);Concat(S,Sub2,Sub1);StrDestroy(Sub1);StrDestroy(Sub2);return ok;}//StrDeleteStatus StringOperation::StrDestroy(HString &S){if(S.ch){delete S.ch;S.ch=NULL;}//ifreturn ok;}//StrDestroyvoid main(){char str[12]="abcssasdsss",str1[4]="sss",str2[4]="vvv";StringOperation SOP;HString S,T,V;S.ch=NULL;T.ch=NULL,V.ch=NULL;SOP.StrAssign(S,str,11);SOP.StrAssign(T,str1,3);SOP.StrAssign(V,str2,3);cout<<"串S：";SOP.StrOutput(S);cout<<endl;cout<<"串T：";SOP.StrOutput(T);cout<<endl;cout<<"串V：";SOP.StrOutput(V);cout<<endl;cout<<"\n"<<"采用KMP算法进行模式匹配：";cout<<SOP.Index_KMP(S,T,1)<<endl;cout<<"用串V替换S中与T相等的所有子串：";SOP.Replace(S,T,V);SOP.StrOutput(S);cout<<endl;cout<<"在串S的第10个字符之前插入串T：";SOP.StrInsert(S,10,T);SOP.StrOutput(S);cout<<endl;cout<<"删除串S从第2个字符起长度为3的子串：";SOP.StrDelete(S,2,3);SOP.StrOutput(S);cout<<endl;}//main