Here\'s the link for the .txt files if needed: https://www.dropbox.com/sh/h2y27k

Question

Here's the link for the .txt files if needed: https://www.dropbox.com/sh/h2y27kbuytaz5da/AAAnwCbmvLNnzAMFen4EpKfKa?dl=0

Here's the main.cpp that can't be changed:

/*main.cpp*/

#include <iostream>
#include <fstream>
#include <string>
#include <cstdlib>

using namespace std;

//
// function declarations:
//
int GetFileStats(string filename, string& firstKey, string& firstValue);
bool SearchForKey(string filename, string key, string& value, int& rank);

//
// main:
//
int main()
{
string filename;

cin >> filename;

cout << "**Starting**" << endl;
cout << "File: '" << filename << "'" << endl;
cout << endl;

//
// First, let's get some statistics about the data file:
//
int N, rank;
string key, value;
bool found;

N = GetFileStats(filename, key, value);

cout << "# of entries: " << N << endl;
cout << "Top-ranked: (" << key << ", " << value << ")" << endl;
cout << endl;

//
// Now let's input keys from the keyboard and look for them in the file:
//
cin >> key;

while (key != "#")
{
found = SearchForKey(filename, key, value, rank);
  
if (found == true)
{
cout << ">>Found key: " << key << endl;
cout << " Value= " << value << endl;
cout << " Rank= " << rank << endl;
}
else // not found:
{
cout << ">>Not found: " << key << endl;
}
  
cin >> key;
}

cout << endl;
cout << "**End**" << endl;

return 0;
}

Here's the search.cpp that needs to be changed for the assignment:

/*search.cpp*/

#include <iostream>
#include <fstream>
#include <string>
#include <cstdlib>

using namespace std;

//
// GetFileStats
//
// Returns the # of (key, value) pairs in the given file. Also returns the first (key, value)
// pair via the parameters firstKey and firstValue.
//
// NOTE: it is assumed the file contains at least one (key, value) pair, in this format:
//
// value key
// value key
// value key
// # #
//
// where value and key are one word strings (or numbers that will be input as strings).
// If the file cannot be opened, the program will be exited.
//
int GetFileStats(string filename, string& firstKey, string& firstValue)
{
//
// Initialize return value / parameters:
//
firstKey = "?";
firstValue = "?";
int N = 0;

//
// TODO: open and read the (key, value) pairs from the file. The goal is
// to simply count how many pairs there are and return this value N. Also,
// we need to return the first (key, value) pair via the firstKey and
// firstValue parameters; just assign to the parameters to "return" the
// values. Don't forget to close the file when you're done.
//




return N;
}

//
// SearchForKey
//
// Opens the given file, searches for the given key, and if found, returns true; if the
// key is not found then false is returned.
//
// If the key is found, the value will be returned via the "value" parameter; likewise
// the rank will be returned via the "rank" parameter. The rank is simply the line #
// where the (key, value) pair was found: 1 for first line, 2 for second line, etc.
// If the key is not found, value and rank should be ignored.
//
// NOTE: it is assumed the file contains at least one (key, value) pair, in this format:
//
// value key
// value key
// value key
// # #
//
// where value and key are one word strings (or numbers that will be input as strings).
// If the file cannot be opened, the program will be exited.
//
bool SearchForKey(string filename, string key, string& value, int& rank)
{
//
// initialize return value / parameters:
//
value = "<<not found>>";
rank = 0;
bool found = false; // not found:

//
// TODO: search for the key, and if found, we want to return the associated value.
// But we also need to return the "rank" via the rank parameter; the rank is the
// line number where the (key, value) appears: 1 for first line, 2 for second
// line, and so on. Finally, return true if key was found, false if not.
//
// Don't forget to close the file when you're done.
//





return found;
}

Summary: searching text files for (key, value) pairs, e.g. movies and their total revenue. Google collects all sorts of interesting data: what words appear most frequently in searches? What web sites are most commonly searched using Alexa? What are the most popular baby names? For example, the data file 'words-by-freq.txt ranks the English words used most commonly in searches. Here's the start of the file: 5627187200 the 3395006400 of 2994418400 and 2595609600 to The words are listed by rank, so the is the most frequently searched word with a frequency of "5627187200". The 2nd most frequently searched word is "of, with a frequency of "3395006400", and so on. The file ends with # and #. In general, we call this type of file a "(key, value)" file, since the data comes in pairs, and the "key" uniquely identifies the 'value. Note that the value is on the left, and the key is on the right. This implies you should view these types of files like this value key value key value key Note that you should view the values and keys as strings-often the values are integers and the keys are strings, but it's dangerous to assume this is always true. Instead, treat all input data as strings, and use string variables. In this exercise, you're going to write a complete C++ program that searches data from a (key, value) input file, outputting some statistics, values, and ranks. The main0 program is written for you (and cannot be modified); your job is to implement the 2 functions in "search.cpp" that do the work of opening, inputting, and searching the input file. First, here's an example input sequence for the program:

Explanation / Answer

#include"search.cpp"
#include <iostream>
#include <fstream>
#include <string>
#include <cstdlib>
using namespace std;
//
// function declarations:
//
int GetFileStats(string filename, string& firstKey, string& firstValue);
bool SearchForKey(string filename, string key, string& value, int& rank);

//
// main:
//
int main()
{
string filename;
cout<<" Enter the file name: ";
cin >> filename;

cout << "**Starting**" << endl;
cout << "File: '" << filename << "'" << endl;
cout << endl;

//
// First, let's get some statistics about the data file:
//
int N, rank;
string key, value;
bool found;

N = GetFileStats(filename, key, value);

cout << " # of entries: " << N << endl;
cout << " Top-ranked: (" << key << ", " << value << ")" << endl;
cout << endl;

//
// Now let's input keys from the keyboard and look for them in the file:
//
cout<<" Enter the key to search: ";
cin >> key;
// Loops till key value is not '#'
while (key != "#")
{
found = SearchForKey(filename, key, value, rank);
// Checks the found status if it is true display the information
if (found == true)
{
cout << " >>Found key: " << key << endl;
cout << " Value= " << value << endl;
cout << " Rank= " << rank << endl;
}
else // not found:
{
cout << ">>Not found: " << key << endl;
}
// Accepts key value from the user
cout<<" Enter the key to search: ";
cin >> key;
}// End of while loop

cout << endl;
cout << "**End**" << endl;

return 0;
} //End of main function

Sample Run:

Enter the file name: words-by-freq.txt
**Starting**
File: 'words-by-freq.txt'

# of entries: 8000

Top-ranked: (the, 5627187200)

Enter the key to search: the

>>Found key: the
Value= 5627187200
Rank= 1

Enter the key to search: c++
>>Not found: c++

Enter the key to search: meanwhile

>>Found key: meanwhile
Value= 1692630
Rank= 4152

Enter the key to search: you

>>Found key: you
Value= 604890300
Rank= 17

Enter the key to search: #

**End**

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