Question

File IO Java question

• Ask the user to specify the file name to open for reading

• Get the number of data M (M<= N) he wants to read from file

• Read M numbers from the file and store them in an array

• Compute the average and display the numbers and average.

Answer 1

Note: Could you plz go through this code and let me know if u need any changes in this.Thank You
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// fileDataNums.txt

23
34
45
56
67
76
65
54
43
32
21
78
89
90
9
8
76
44
55
67
77
88

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// ReadFilenos.java

import java.io.File;
import java.io.FileNotFoundException;
import java.util.Scanner;

public class ReadFilenos {

   public static void main(String[] args) throws FileNotFoundException {

       int m,n=0;
       double sum=0;
       /*
       * Creating an Scanner class object which is used to get the inputs
       * entered by the user
       */
       Scanner sc = new Scanner(System.in);
       System.out.print("Enter m:");
       m=sc.nextInt();
      
      
       Scanner fileOpen = new Scanner(new File("fileDataNums.txt"));
while(fileOpen.hasNext())
{
   fileOpen.nextDouble();
   n++;
}
  
fileOpen.close();
  
if(m<=n)
{
   double nos[]=new double[m];
   fileOpen=new Scanner(new File("fileDataNums.txt"));
   for(int i=0;i<m;i++)
   {
       nos[i]=fileOpen.nextDouble();
       sum+=nos[i];
   }
   fileOpen.close();
   System.out.println("Displaying the nos :");
   for(int i=0;i<m;i++)
   {
       System.out.print(nos[i]+" ");
   }
   System.out.println("\nAverage :"+(sum/m));
}
else
{
   System.out.println("** Invalid input **");
}
   }

}
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Output:

Enter m:10
Displaying the nos :
23.0 34.0 45.0 56.0 67.0 76.0 65.0 54.0 43.0 32.0
Average :49.5

_______________Could you plz rate me well.Thank You