技術標籤：c++ primer筆記

textQuery.h

class QueryResult; // declaration needed for return type in the query function
class TextQuery {
public:
#ifdef TYPE_ALIAS_DECLS
	using line_no = std::vector<std::string>::size_type;
#else
	typedef std::vector<std::string>::size_type line_no;
#endif
	TextQuery
 
(std::ifstream&);
    QueryResult query(const std::string&) const; 
    void display_map();        // debugging aid: print the map
private:
    std::shared_ptr<std::vector<std::string>> file; // input file
    // maps each word to the set of the lines in which that word appears
    std::
 
map<std::string, std::shared_ptr<std::set<line_no>>> wm;  

	// canonicalizes text: removes punctuation and makes everything lower case
    static std::string cleanup_str(const std::string&);
};

queryResult.h

class QueryResult {
friend std::ostream& print(std::ostream&, const
 
 QueryResult&);
public:
	typedef std::vector<std::string>::size_type line_no;
	typedef std::set<line_no>::const_iterator line_it;
	QueryResult(std::string s, 
	            std::shared_ptr<std::set<line_no>> p, 
	            std::shared_ptr<std::vector<std::string>> f):
		sought(s), lines(p), file(f) { }
	std::set<line_no>::size_type size() const  { return lines->size(); }
	line_it begin() const { return lines->cbegin(); }
	line_it end() const   { return lines->cend(); }
	std::shared_ptr<std::vector<std::string>> get_file() { return file; }
private:
	std::string sought;  // word this query represents
	std::shared_ptr<std::set<line_no>> lines; // lines it's on
	std::shared_ptr<std::vector<std::string>> file;  //input file
};

std::ostream &print(std::ostream&, const QueryResult&);

void test(){
// open the file from which user will query words
        ifstream infile;
        infile.open("E:/temp/queryText");


        // infile is an ifstream that is the file we want to query
        TextQuery tq(infile);  // store the file and build the query map

        // iterate with the user: prompt for a word to find and print results
        while (true) {
            cout << "enter word to look for, or q to quit: ";

            // stop if we hit end-of-file on the input or if a 'q' is entered
            string s;
            if (!(cin >> s) || s == "q") 
                break;

            // run the query and print the results
            print(cout, tq.query(s)) << endl;
        } 
}

queryText file:

Some programs read cin for their input.
Sample data files are in the data directory:

     File           Programs that use that input file
     ----           --------
   storyDatafile    usealloc
   storyDatafile    querymain
   Alice            querymain
   alloc            allocPtr  
   alloc            allocSP

Programs not listed above print output and do
not read any input

result: