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#include "stdafx.h"
 
#include <iostream>
#include <string>
 
using namespace std;
 
int main(){
   string s,str,x;
   cout<<"Enter the sentence: ";
   getline(cin, s);
      cout<<"Enter the letter's combination: ";
   getline(cin, str);
  size_t i=0;
   while (i<s.length())
   {
   if ((s[i]==' ') || (i+1==s.length())) {
   string ex=s.substr(0,i+1);
   if (ex.find(str)==string::npos) x+=ex;
   s.erase(0,i+1);
   i=0;
   }
   else i++;
   }
   cout<<x<<endl;
   system("pause");
    return 0;
}

#include <iostream>
using std::cout;
using std::endl;
#include <string>
using std::string;
#include <regex>
using std::regex;
using std::regex_search;
using std::smatch;
using std::regex_replace;
 
string f1(const string& str,string s)
{
    string s1="([^ ]*)"; s1+=s; s+="([^ ]*)";
    return regex_replace(str,regex(s1),string(""));
}
 
string f2(string str,string s)
{
    string s1="([^ ]*)"; s1+=s; s+="([^ ]*)";
    smatch sm;
    string rez="";
    while(regex_search(str, sm,regex(s1)))
    {
        rez+=sm[0];
        rez+=' ';
        str=sm.suffix();
    }
    return rez;
}
 
int main()
{
    string str="hellow bee da eesebta deeda";
    cout <<"str= "<<str<<endl;
 
    string ydalit6=f1(str,"da");
    string iz69t6 = f2(str,"da");
 
    cout <<"ydalit6= "<<ydalit6<<endl;
    cout <<"iz69t6= "<<iz69t6<<endl;
 
    return 0;
}