C/C++文字作成処理

12603 ワード

C:
strncpy(a,b,5);

a[5]='0';



char a[10];

memset(a,'#',sizeof(a));

a[10]='0';


1.      

   strlen(st);



2.      

   strcmp(st1,st2);

   strncmp(st1,st2,n);    st1,st2  n     。



3.   

   strcat(st1,st2);

   strncat(st1,st2,n);   n     st2  n  st1,      '0'。



4.   

   strcpy(st1,st2);

   strncpy(st1,st2,n); n    st2  n  st1,     '0'。



5.   

   where = strchr(st,ch)   ch      。

   where = strspn(st1,st2);      。

   where = strstr(st1,st2);





C++:



<string>

string str;

1.      

   len = str.length();

   len = str.size();



2.      

         

      :

   str1.compare(str2); 

   str1.compare(pos1,len1,str2,pos2,len2);    ,0 , 。

   nops     。



3.   

   str1 += str2;

    

   str1.append(str2);

   str1.append(str2.pos2,len2);

   

4.      

   str2 = str1.substr();

   str2 = str1.substr(pos1);

   str2 = str1.substr(pos1,len1);

   string a=s.substr(0,4);       //     s    0       4  



  





5.      

   where = str1.find(str2);

   where = str1.find(str2,pos1); pos1  str1      。

   where = str1.rfind(str2);      。



6.      

         。

   str1.insert(pos1,str2);

   str1.insert(pos1,str2,pos2,len2);

   str1.insert(pos1,numchar,char);    numchar     ,char      



 。



7.      

   str1.replace(pos1,str2);

   str1.replace(pos1,str2,pos2,len2);



8.      

   str.erase(pos,len)

   str.clear();



9.      

   swap(str1,str2);



10. C --> C++

   char *cstr = "Hello";

   string str1;

   cstr = cstr;

   string str2(cstr);



  ACMer  ,C        C++   、  ,   C        。



C++ string     

string      :



string(const char *s);    // c   s   



string(int n,char c);     // n   c   



  ,string                 , string s1;string 



s2="hello";       。    string           



length_error  



string      :



const char &operator[](int n)const;



const char &at(int n)const;



char &operator[](int n);



char &at(int n);



operator[] at()          n      , at        ,



       out_of_range  ,     []       。



const char *data()const;//     null   c    



const char *c_str()const;//     null   c   



int copy(char *s, int n, int pos = 0) const;//      pos   n   



    s           ,         



string     :



int capacity()const;    //      ( string             



   )



int max_size()const;    //  string               



int size()const;        //          



int length()const;       //          



bool empty()const;        //         



void resize(int len,char c);//          len,    c     



  string        :



string      operator>>  //    ,       operator<<    



  。



  getline(istream &in,string &s);//      in       s ,  



  'n'  。



 



string   :



string &operator=(const string &s);//    s       



string &assign(const char *s);// c     s  



string &assign(const char *s,int n);// c   s   n     



string &assign(const string &s);//    s       



string &assign(int n,char c);// n   c        



string &assign(const string &s,int start,int n);//    s  start   



n          



string &assign(const_iterator first,const_itertor last);// first last 



            



 



string   :



string &operator+=(const string &s);//    s           



string &append(const char *s);   // c     s          



string &append(const char *s,int n);// c     s  n        



     



string &append(const string &s);    // operator+=()



string &append(const string &s,int pos,int n); //    s  pos   n 



             



string &append(int n,char c);        //          n   c



string &append(const_iterator first,const_iterator last);//    first 



last                



 



string   :



bool perator==(const string &s1,const string &s2)const;//        



   



   ">","<",">=","<=","!="            ;



int compare(const string &s) const;//        s   



int compare(int pos, int n,const string &s)const;//        pos  



 n          s   



int compare(int pos, int n,const string &s,int pos2,int n2)const;//   



     pos   n          s pos2   n2         



   



int compare(const char *s) const;



int compare(int pos, int n,const char *s) const;



int compare(int pos, int n,const char *s, int pos2) const;



compare   >   1,<   -1,==   0  



string   :



string substr(int pos = 0,int n = npos) const;//  pos   n      



   string   :



void swap(string &s2);    //        s2  



 



string      :



int find(char c, int pos = 0) const;// pos      c         



int find(const char *s, int pos = 0) const;// pos       s    



    



int find(const char *s, int pos, int n) const;// pos       s  n



           



int find(const string &s, int pos = 0) const;// pos       s   



     



//           ,    string::npos  



int rfind(char c, int pos = npos) const;// pos          c   



     



int rfind(const char *s, int pos = npos) const;



int rfind(const char *s, int pos, int n = npos) const;



int rfind(const string &s,int pos = npos) const;



// pos           s  n                 , 



       ,     string::npos  



int find_first_of(char c, int pos = 0) const;// pos      c    



    



int find_first_of(const char *s, int pos = 0) const;



int find_first_of(const char *s, int pos, int n) const;



int find_first_of(const string &s,int pos = 0) const;



// pos            s  n               。  



    



string::npos



int find_first_not_of(char c, int pos = 0) const;



int find_first_not_of(const char *s, int pos = 0) const;



int find_first_not_of(const char *s, int pos,int n) const;



int find_first_not_of(const string &s,int pos = 0) const;



//             s         ,    string::npos



int find_last_of(char c, int pos = npos) const;



int find_last_of(const char *s, int pos = npos) const;



int find_last_of(const char *s, int pos, int n = npos) const;



int find_last_of(const string &s,int pos = npos) const;



int find_last_not_of(char c, int pos = npos) const;



int find_last_not_of(const char *s, int pos = npos) const;



int find_last_not_of(const char *s, int pos,  int n) const;



int find_last_not_of(const string &s,int pos = npos) const;



//find_last_of find_last_not_of find_first_of find_first_not_of  , 



         



 



string      :



string &replace(int p0, int n0,const char *s);//   p0   n0   , 



  p0    s



string &replace(int p0, int n0,const char *s, int n);//  p0   n0  



 ,   p0      s  n   



string &replace(int p0, int n0,const string &s);//   p0   n0   ,



   p0    s



string &replace(int p0, int n0,const string &s, int pos, int n);//  p0 



  n0   ,   p0    s  pos   n   



string &replace(int p0, int n0,int n, char c);//  p0   n0   ,  



 p0   n   c



string &replace(iterator first0, iterator last0,const char *s);// [first0



,last0)           s



string &replace(iterator first0, iterator last0,const char *s, int n);// 



[first0,last0)        s  n   



string &replace(iterator first0, iterator last0,const string &s);// 



[first0,last0)         s



string &replace(iterator first0, iterator last0,int n, char c);// [first0



,last0)        n   c



string &replace(iterator first0, iterator last0,const_iterator first, 



const_iteratorlast);// [first0,last0)        [first,last)  



    string     :



string &insert(int p0, const char *s);



string &insert(int p0, const char *s, int n);



string &insert(int p0,const string &s);



string &insert(int p0,const string &s, int pos, int n);



// 4    p0       s pos    n   



string &insert(int p0, int n, char c);//    p0   n   c



iterator insert(iterator it, char c);// it     c,         



  



void insert(iterator it, const_iterator first, const_iterator last);// it



   [first,last)     



void insert(iterator it, int n, char c);// it   n   c



 



string      



iterator erase(iterator first, iterator last);//  [first,last)    



   ,           



iterator erase(iterator it);//  it     ,           



string &erase(int pos = 0, int n = npos);//  pos   n   ,    



     



 



string       :



string               iterator,              



 ,       ,        。



 string::iterator string::const_iterator       ,const_iterator 



         。        :



const_iterator begin()const;



iterator begin();                //  string     



const_iterator end()const;



iterator end();                    //  string            



const_iterator rbegin()const;



iterator rbegin();                //  string          



const_iterator rend()const;



iterator rend();                    //  string          rbegin



 rend           ,       



string::reverse_iterator,string::const_reverse_iterator  



 



      :



    ostringstream istringstream    ,<sstream>    



  :



    string input("hello,this is a test");



    istringstream is(input);



    string s1,s2,s3,s4;



    is>>s1>>s2>>s3>>s4;//s1="hello,this",s2="is",s3="a",s4="test"



    ostringstream os;



    os<<s1<<s2<<s3<<s4;



    cout<<os.str();