//Your keyboard is not working properly... it's as below: // if you press < it works like home key and whatever you type hence forth is to be written as start of string... For example; ABC it works like end key and whatever you type hence forth is to be written at end of string... For example; ABCEF would be DZABCEF // if you press * it works like delete key of current position... For example, ABD*E would be ABE Also , ABF would be CEABF // initially your num lock is on and you can have num printed if you type.... # behaves like on off... pressing two times would again result into on... for example , AB1#D234 would be AB1D And, AB1#D2#3 would be AB1D3 #include #include using namespace std; string receivedText_Old(string S) { string output = ""; bool isNumOn = true; int L = S.length(); int curPos = 0; for(int i=0;i')//END key...goes at the end { curPos = output.length(); continue; } else if(S[i] == '*') // deletes last character { if(output.length()>0) { string strLeft = output.substr(0,curPos-1); string strRight = output.substr(curPos,output.length()-curPos); //cout << strRight << "--->" << strLeft<<"--->" << endl; output = strLeft + strRight;//output.substr(0,output.length()-1); --curPos; } continue; } else if(S[i] == '#') // num lock on / off { isNumOn=!isNumOn; continue; } output.insert(curPos, string(1,S[i])); ++curPos; } return output; } string receivedText_Bug(string S) { bool isNumOn = true; bool isAtHome = true; bool isAtEnd = false; deque dq; dq.push_back(""); dq.push_front(""); int L = S.length(); for(int i=0;i')//END key...goes at the end { isAtHome = false; isAtEnd = true; string str = dq.back(); dq.push_front(str); dq.push_back(""); continue; } else if(S[i] == '*') // deletes last character { if(isAtHome) { string str = dq.front(); str.pop_back(); dq.push_front(str); } if(isAtEnd) { string str = dq.back(); str.pop_back(); dq.push_back(str); } continue; } else if(S[i] == '#') // num lock on / off { isNumOn=!isNumOn; continue; } if(isAtHome) { string str = dq.front(); str.push_back(S[i]); dq.push_front(str); } if(isAtEnd) { string str = dq.back(); str.push_back(S[i]); dq.push_back(str); } } return dq.front() + dq.back(); } string receivedText(string& s) { deque d(1); int deqIndex = 0; bool isNumOn = true; for(auto& c : s ) { if (isdigit(c) && isNumOn==false) { continue; } else if(c == '#') // num lock on / off { isNumOn=!isNumOn; continue; } else if( c == '<' ) { d.push_front( "" ); deqIndex = 0; } else if( c == '>' ) { d.push_back( "" ); deqIndex = d.size() - 1; } else if( c == '*' ) { while( d[deqIndex].empty() && deqIndex > 0 ) { --deqIndex; } if( !d[deqIndex].empty() ) d[deqIndex].pop_back(); } else { d[deqIndex] += c; } } string str = ""; for( const auto& i : d ) { str += i; } return str; } int main() { string S = "Heo";//"Heo"; cout << receivedText_Old(S) << endl; cout << receivedText(S); return 0; }

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