Question

Please write a C++ program to read a list of numbers from a datafile, and calculate the average, lowest and largest number.

Please use the following command to copy the datafile scores.txt to your home directory:

Please use end-of-file loop to read all the floating-point numbers from the datafile scores.txt.
Please display the average, lowest and largest number of all the numbers in the datafile.
Please create a function to process the datafile, and call the dataProcessing function in the main function.

Answer 1

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Where we have to save the input file ..???

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// scores.txt (Input file)

78
89
98
87
76
65
55
99
87
54

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#include <fstream>
#include <iostream>
#include <iomanip>
using namespace std;
// function declarations
void dataProcessing(double nos[], int total_num, double& min, double& max, double& avg);
int main()
{
// Declaring variables
int total_num=0;
double min, max;
double avg;
string filename="scores.txt";
// defines an input stream for the data file
ifstream dataIn;
  
double num;
dataIn.open(filename.c_str());
//checking whether the file name is valid or not
if(dataIn.fail())
{
cout<<"** File Not Found **";
return 1;
}
else
{
//Reading the data from the file
while(dataIn>>num)
{
total_num++;
}
dataIn.close();
  
// Creating array dynamically
double* nos = new double[total_num];
  
dataIn.open(filename.c_str());
for(int i=0;i<total_num;i++)
{
dataIn>>num;
nos[i]=num;
}
dataIn.close();
  
dataProcessing(nos, total_num, min, max, avg);
  

// Displaying the output
cout << "Minimum :" << min << endl;
cout << "Maximum :" << max << endl;
cout << "Average :" << avg << endl;
}
  
  

return 0;
}
// This function will find out the minimum , maximum and average score in array
void dataProcessing(double nos[], int total_num, double& min, double& max, double& avg)
{
min=nos[0];
max=nos[0];
double sum=0;
for(int i=0;i<total_num;i++)
{
if(min>nos[i])
{
min=nos[i];
}
if(max<nos[i])
{
max=nos[i];
}
sum+=nos[i];
}
avg=sum/total_num;
}

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Output:

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