Count the top 10 movies in the box office and save them to another file.

Today, I saw a pen question: Given a file (M. dat), which stores box office statistics for various movies. The format is as follows:

2012 Sony $769.7
"Harry Potter and the death Saint (I)" Warner Brothers $952.0
Star Wars 20th century forks $775.4
Trigger/DreamWorks for monster Shrek 4 $750.0
Avatar 20th Century Fox $2,782.2
Warner Brothers for Harry Potter and the flame cup $895.9
"Harry Potter and the Half-Blood Prince" Warner Brothers $934.0
New Line of Lord of the Rings 2: double tower qibing $925.3
Batman prequel 2: Dark Knight Warner Brothers $1,001.9
Harry Potter and the magic stone Warner Brothers $974.7
Bottom story Disney $867.9
Kung fu pandatv/DreamWorks $631.7
Pirates of the Caribbean 3: The end of the world Disney $961.0
Warner Brothers, the prisoner of Harry Potter and Azkaban, $795.6
E. T. Global $792.9
Raiders 4: The Kingdom of the crystal skull palaman $786.6
"Lord of the Rings 3: Return of the King" New Line $1,119.1
Monstrok 2 DreamWorks $919.8
Toys Story 3 Disney $1,063.2
Hacker Empire 2: reloaded into battle Warner Brothers $742.1

.......

Write a program to count the top 10 movies at the box office and save the statistical results to another file. Try using C ++ and share the following code: (GCC compilation in Linux)

For GCC compilation, two command line parameters must be input during execution, such as./A. Out.M. dat Li. dat(M. dat is the source box office file, and Li. dat is the file that stores the first 10)

# Include <iostream> # include <fstream> # include <vector> # include <algorithm> using namespace STD; Class movie {public: // reload the input operation friend istream & operator> (istream & is, Movie & movie) {return is> movie. m_title> movie. m_comp> movie. m_gross;} // reload the output operation friend ostream & operator <(ostream & OS, const Movie & movie) {return OS <movie. m_title <<'' <movie. m_comp <''<movie. m_gross;} // reload the less than sign for list sorting bool Operator <(const Movie & movie) const {return gross ()> movie. gross ();} PRIVATE: // convert the string read from the file to double. Double gross (void) const {string STR (m_gross); size_t Pos = 0; while (Pos = Str. find_first_of ("$,", POS ))! = // Remove "$" and "," string: NPOs) Str. erase (Pos, 1); Return atof (Str. c_str ();} string m_title; // movie name string m_comp; // produced company name string m_gross; // box office}; // read the file, store the read results to the vector <movie> & vmbool read (const char * file, vector <movie> & VM) {ifstream ifs (File); If (! IFS) {perror ("failed to open the box office file"); Return false;} movie; while (IFS> movie) // call the overloaded> operator VM. push_back (movie); ifs. close (); Return true;} // write the data in the vector <movie> & VM into the file bool write (const char * file, const vector <movie> & VM) {ofstream ofs (File); If (! OFS) {perror ("failed to open the ranking file"); Return false ;}for (vector <movie >:: const_iterator it = VM. Begin (); it! = VM. end (); ++ it) ofs <* It <Endl; // call the overloaded <operator ofs. close (); Return true;} int main (INT argc, char * argv []) {// determine whether the number of command line parameters is legal if (argc <3) {cerr <"Usage:" <argv [0] <"<box office File> <ranking File>" <Endl; Return-1 ;} vector <movie> VM; If (! Read (argv [1], Vm) Return-1; sort (VM. begin (), VM. end (); // sort the elements in the VM if (VM. size ()> 10) VM. resize (10); // retrieve the first 10 if (! Write (argv [2], Vm) Return-1; return 0 ;}

Count the top 10 movies in the box office and save them to another file.