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#include <iostream>
#include <fstream> // I/O
#include <iomanip> // For setw()
using namespace std;
ofstream outputfile("output.txt");
const int MAX_FILE_NAME = 35; // Maximum file name length
const int MAX_NUMBER_SCORES = 40; // Maximum number of values in array
void open_input(ifstream& input, char name[]); // Get file name & Open file
void read_values(ifstream& input, double v[], int size, int& used); // Read values from file
double find_average(ifstream& input, double& average); // Find avg values
void output(const char name[], const double v[], int n, double find_average, ostream& os = cout); // Print results
int main()
// Parameters: None
// Returns: Zero
// Calls: open_input(), find_average(), output()
{ char again; // Does user want to go through loop again?
char file_name[MAX_FILE_NAME + 1]; // Name of file to be processed
ifstream input_numbers; // For working with input file
double average = 0.0;
double avag = 0;
int num_scores; // Number of scores in file
cout << "This program can find the average numbers in a file\n"
<< "of doubles." << MAX_NUMBER_SCORES << " floating-point values.\n" << endl;
system("pause"); // Hold message on screen until key is pressed
do
{
//system("cls"); // Clear screen
open_input(input_numbers, file_name, scores); // Get file name & open file
find_average(input_numbers, scores, num_scores, avag); // Find average values in file
read_values(input_numbers, scores,
MAX_NUMBER_SCORES, num_scores); // Read values
input_numbers.close(); // Close file
if (num_scores > 0)
{ find_average(scores, num_scores, average); // Find average of values in array
output(file_name, scores, num_scores, avag);
output(file_name, scores, num_scores, average, outputfile); // and outputfile
}
else
{ cout << "\n\n\aNo data in file: " << file_name << endl;
}
cout << "\nDo you want to process another file (Y/N)? ";
cin >> again;
cin.ignore(256, '\n'); // Remove Enter key from keyboard buffer
} while ( again == 'y' || again == 'Y');
cout << "\nEnd of Program!" << endl;
return 0;
} // End of main()
void open_input(ifstream& input, char name[]) //Open file, exit on error
// Parameters: Variables for input file reference and input file name
// Returns: None
// Calls: None
{ int count = 0; // Count number of tries
do // Continue until we get a valid file name and can open file
{
count++;
if (count != 1) // Issue error message if we are trying again.
{ cout << "\n\aInvalid file name or file does not exist. Please try again."
<< endl;
}
cout << "\nEnter the input file name (maximum of " << MAX_FILE_NAME
<< " characters please)\n:> ";
cin.get(name, MAX_FILE_NAME + 1);// Gets at most MAX_FILE_NAME characters
cin.ignore(256, '\n'); // Remove Enter key from keyboard buffer
input.clear(); // Clear all error flags, if any, from prev try
input.open(name, ios_base::in); // Open only if file exists
} while (input.fail() ); // If can't open file, try again
} // End of open_input()
void read_values(ifstream& input, double v[], int size, int& used) // Read values
// Parameters: Variables for file reference, variable for array reference,
// value for array size and variable for number of values in array
// Returns: None
// Calls: None
{
double value; // Value from file
int count = 0; // Count number of values in file
while (count < size && input >> value) // Continue as long as there is
// room in the array and we can read
{ v[count] = value; // a number from file.
count ++;
}
used = count;
} // End of read_values()
void find_average(const double v[], int n, double& average) // Find average of values
// Parameters: Variables for array reference, value for number of values
// and variables for average of values
// Returns: None
// Calls: None
{
int i; // Array index and loop counter
average = find_average = v[0];
for (i = 1; i < n; i++) // Start with 1 since max & min initialized to v[0]
{
if (v[i] > average) average = v[i];
if (v[i] < average) average = v[i];
}
} // End of find_average()
double find_average(ifstream& input, double& average) // Find max & min values
// Parameters: Variables for file reference and max and min values
// Returns: None
// Calls: None
{
double avag;
double sum = 0;
int count = 0;
while (input >> avag) // Continue as long as we can read a number from file.
{
sum += avag;
count = count + 1;
}
average = sum/count;
return sum/count;
} // End of average file
void output(const char name[], double average, ostream& os) // Print results
// Parameters: File name, max & min values from file, output stream
// Returns: None
// Calls: None
{ os << "\n\nInput your File Name Please : " << name << endl;
os << "Your average : " << setw(8) << average<< endl;
}
void output(const char name[], const double v[], int n,
double max, double min, ostream& out)
// Parameters: File name, array reference, number of values and max & min values
// Returns: None
// Calls: None
{ int i; // Array index and loop counter
out.setf(ios::fixed);
out.setf(ios::showpoint);
out.precision(1);
out << "\n\nInput File Name: " << name << endl;
out << "\nFile Contents:" << endl;
for (i = 0; i < n; )
{ out << setw(8) << v[i];
if ( ++i % 5 == 0) out << "\n"; // Print only 5 values per line
}
if ( i % 5 != 0) out << "\n"; // Newline if last line is short
out << "\nLargest Number in File: " << setw(8) << max << endl;
out << "Smallest Number in File: " << setw(8) << min << endl;
} // End of output()
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