header - Multiple Source File Problem in C++ -

i had a problem in implementing multiple source file

my function this:

inline bool textcontains(char *text, char ch) {   while ( *text ) {     if ( *text++ == ch )       return true;   }   return false; }  void split(char *text, char *delims, vector<string> &words) {   int beg;   (int = 0; text[i]; ++i) {      while ( text[i] && textcontains(delims, text[i]) )       ++i;      beg = i;      while ( text[i] && !textcontains(delims, text[i]) )       ++i;       words.push_back( string(&text[beg], &text[i]) );     } }  string convertint(int number) {    stringstream ss;    ss << number;    return ss.str(); }   string dateformatchecker(const char *date){ string strdate=date; char getdate[50]; strcpy_s(getdate, strdate.c_str());  vector<string> checkdate; split( getdate, "-", checkdate ); int year, month, day; year=atoi(checkdate[0].c_str()); month=atoi(checkdate[1].c_str()); day=atoi(checkdate[2].c_str());  string checkyear, checkmonth, checkday, checkhour, checkminute, checksecond;          checkyear = convertint(year);         if(month<10){         checkmonth = "0" + convertint(month);         }         else{         checkmonth = convertint(month);         }         if(day<10){         checkday = "0" + convertint(day);         }         else{         checkday = convertint(day);         }          if (checkyear.size() != checkdate[0].size()||             checkmonth.size() != checkdate[1].size()||             checkday.size() != checkdate[2].size()){             return "";         } return date; }  string dateandtimeformatchecker(const char *dateandtime){     string strdate=dateandtime;     char getdateandtime[50];     strcpy_s(getdateandtime, strdate.c_str());      vector<string> checkdateandtime;         split( getdateandtime, "-: ", checkdateandtime );     int year, month, day, hour, minute, second;         year=atoi(checkdateandtime[0].c_str());         month=atoi(checkdateandtime[1].c_str());         day=atoi(checkdateandtime[2].c_str());         hour=atoi(checkdateandtime[3].c_str());         minute=atoi(checkdateandtime[4].c_str());         second=atoi(checkdateandtime[5].c_str());          string checkyear, checkmonth, checkday, checkhour, checkminute, checksecond;          checkyear = convertint(year);         if(month<10){         checkmonth = "0" + convertint(month);         }         else{         checkmonth = convertint(month);         }         if(day<10){         checkday = "0" + convertint(day);         }         else{         checkday = convertint(day);         }         if(hour<10){         checkhour = "0" + convertint(hour);         }         else{         checkhour = convertint(hour);         }         if(minute<10){         checkminute = "0" + convertint(minute);         }         else{         checkminute = convertint(minute);         }         if(second<10){         checksecond = "0" + convertint(second);         }         else{         checksecond = convertint(second);         }           if (checkyear.size() != checkdateandtime[0].size()||             checkmonth.size() != checkdateandtime[1].size()||             checkday.size() != checkdateandtime[2].size()||             checkhour.size() != checkdateandtime[3].size()||             checkminute.size() != checkdateandtime[4].size()||             checksecond.size() != checkdateandtime[5].size()){             return "";         }      return dateandtime;      }  string formatposdataxml (const char * sequencenumber, const char * retailstoreid, const char * workstationid, const char * businessdaydate, const char * begindatetime, const char * starttranstime, const char * endtranstime, const char * enddatetime, const char * rawdata){  string output;  string bdd, bdt, stt, ett, edt;  bdd = dateformatchecker(businessdaydate); bdt = dateandtimeformatchecker(begindatetime); stt = dateandtimeformatchecker(starttranstime); ett = dateandtimeformatchecker(endtranstime); edt = dateandtimeformatchecker(enddatetime);  cout << "<transaction>\n\t<retailstoreid>"      << retailstoreid   << "</retailstoreid>\n\t<workstationid>"      << workstationid   << "</workstationid>\n\t<sequencenumber>"      << sequencenumber  << "</sequencenumber>\n\t<businessdaydate>"      << bdd             << "</businessdaydate>\n\t<begindatetime>"      << bdt             << "</begindatetime>\n\t<starttranstime>"      << stt             << "</starttranstime>\n\t<endtranstime>"      << ett             << "</endtranstime>\n\t<enddatetime>"      << edt             << "</enddatetime>\n\t<rawdata>"      << rawdata         << "</rawdata>\n</transaction>";  output = _getch(); return output;  }  string getinput(char *data){ vector<string> words;  split( data, ",", words );    char sn[11], rsi[200], wsi[200], bdd[100], bdt[100], stt[100], ett[100], edt[100], rd[100];    strcpy_s(sn, words[0].c_str());   strcpy_s(rsi, words[1].c_str());   strcpy_s(wsi, words[2].c_str());    strcpy_s(bdd, words[3].c_str());   strcpy_s(bdt, words[4].c_str());   strcpy_s(stt, words[5].c_str());   strcpy_s(ett, words[6].c_str());   strcpy_s(edt, words[7].c_str());   strcpy_s(rd, words[8].c_str());    string posdata;   posdata = formatposdataxml(sn,rsi,wsi,bdd,bdt,stt,ett,edt,rd);  return posdata;  } 

but whenever put in header file :

string getinput(char *data); 

i plenty of errors undeclared identifier, int string redefinition , on...

anyone can me?

i think order of header #includes might source of problem.