Question

[C++]

Using Files—Total and Average Rainfall
Write a program that reads in from a file a starting month name, an ending month name, and then the monthly rainfall for each month during that period. As it does this, it should
sum the rainfall amounts and then report the total rainfall and average rainfall for the period. For example, the output might look like this: During the months of March–June the total rainfall was 7.32 inches and the average monthly rainfall was 1.83 inches. Data for the program can be found in the Rainfall.txt file.
Hint: After reading in the month names, you will need to read in rain amounts until the EOF is reached, and count how many pieces of rain data you read in.

<<ISSUE: My "average monthly rainfall" value returns 5 decimal numbers but it has to be two decimals as ideal output below. Please help to solve this issue.>>

(ideal output)

THE CORRECT OUTPUT OF THE TEST CASE 1 During the months of June - December the total 2 rainfall was 20.12 inches and the average monthly 3 rainfall was 2.87 inches. 4
(current output)

(Rainfall.txt file)

January
May
1.35 2.15 3.03 4.41 5.41

(Current code)

#include
#include
#include
using namespace std;

int main()
{
   ifstream inputFile;
   string sname, ename;
   double val, total=0.0, avg, c=0.0;
   inputFile.open("Rainfall.txt");
  
   inputFile >> sname;
   inputFile >> ename;
  
   if(!inputFile)
   {
   cout << "Rainfall.txt file does not exist in folder" << endl;
   cout << "Please insert Rainfall.txt file in the folder" << endl;
   }
   while(inputFile >> val)
   {
   total=total+val;
   c++;
   }
   avg = total/c;
   inputFile.close();

  
   cout << "During the months of " << sname << "-" << ename << " the total" << endl;
   cout << "rainfall was " << total << " inches and the average monthly" << endl;
   cout << "rainfall was " << avg << " inches." << endl;
  
   return 0;
}

Answer 1

This can be achieved by using 'setprecision()'. This is found inside the '#include <iomanip>' and is used to control the decimal place. The basic syntax of this is: cout << fixed << setprecision(2) << ans;

This would print the ans with 2 decimal place. 'Fixed' is used to round the value. For eg. the number 6.58571 would become 6.59.

Note: I added some more data since using the data provided the average was already in 2 decimal place.

CODE:

#include <iostream>

#include <fstream>

#include <iomanip>

using namespace std;

int main()

{

ifstream inputFile;

string sname, ename;

double val, total=0.0, avg, c=0.0;

inputFile.open("Rainfall.txt");

inputFile >> sname;

inputFile >> ename;

if(!inputFile)

{

cout << "Rainfall.txt file does not exist in folder" << endl;

cout << "Please insert Rainfall.txt file in the folder" << endl;

}

while(inputFile >> val)

{

total=total+val;

c++;

}

avg = total/c;

inputFile.close();

cout << "During the months of " << sname << "-" << ename << " the total" << endl;

cout << "rainfall was " << total << " inches and the average monthly" << endl;

cout << "rainfall was " << fixed << setprecision(2) << avg << " inches." << endl;

return 0;

}

Code Picture:

1 2 3 #include <iostream> #include <fstream> #include <iomanip> using namespace std; int main() 4. 5 6 7 { 8 ifstream inputFile; string sname, ename; double val, total=0.0, avg, c=0.0; inputFile.open("Rainfall.txt"); 9 inputFile >> sname; inputFile >> ename; if(!inputFile) ܒܝܢ 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 cout << "Rainfall.txt file does not exist in folder" << endl; cout << "Please insert Rainfall.txt file in the folder" << endl; } while(inputFile >> val) { total=total+val; C++; } avg = total/c; inputFile.close(); 27

27 28 29 30 31 32 cout << "During the months of " << sname << "-" << ename << " the total" << endl; cout << "rainfall was << total << " inches and the average monthly" << endl; cout << "rainfall was « fixed << setprecision (2) << avg << inches." << endl; 11 return 0; 33 }

OUTPUT:

During the months of January-May the total rainfall was 46.1 inches and the average monthly rainfall was 6.59 inches.

Hope you found this helpful!