Question

Write a program named Review.java and implement the following two methods:

public static int NumberOfElementsLessThanAverage(int[] arr) that returns the number of elements that are less than the average of all elements of the array.

public static int[] countChars(File file), this method reads data from a file and counts the frequency of each alphabetic letters, and returns those numbers as an int array.

the data file name is "data.txt"

Answer 1

import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;

/*
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* and open the template in the editor.
*/

/**
*
* @author Vamsi
*/
public class Review {
  
public static int NumberOfElementsLessThanAverage(int[] arr)
{
//first finding average
double av=0;
for(int i=0;i<arr.length;i++)av=av+arr[i];//ffinding sum
//finding average
av=av/arr.length;
  
int count=0;//to store the count of numbers less than the average
for(int i=0;i<arr.length;i++)if(arr[i]<av)count++;//counting
  
//returning count
return count;
  
}
  
public static int[] countChars(File file) throws FileNotFoundException, IOException
{
//creating frequency array
int feq[]=new int[26];//taking case insensitive
  
//to read file
BufferedReader br = new BufferedReader(new FileReader(file));
  
String st;//reading line by line
while ((st = br.readLine()) != null)
{
//now at each line finding char frequency
  
for(int i=0;i<st.length();i++)
{
  
char c=st.charAt(i);
int n = (int)c;
  
if(n<=91&&65<=n)//capital letters
feq[n-65]++;//increasing feqrency
else if(n<=123&&97<=n)//small letters
feq[n-97]++;
}
  
  
}
//returning frequency
return feq;
}
  
//method to test
public static void main(String argv[]) throws FileNotFoundException, IOException
{
  
File file = new File("C:\\Users\\Vamsi\\Desktop\\data.txt"); //change path as per ur requirement
int feq[] = countChars(file) ;
  
//displaying frequencies
for(int i=0;i<feq.length;i++)
{
char c = (char)(97+i);
System.out.println(c+":"+feq[i]);
  
}
  
  
int count=NumberOfElementsLessThanAverage(feq);
  
System.out.println("NumberOfElementsLessThanAverage :"+count);
}
  
  
}

output:

run:
a:2
b:0
c:0
d:0
e:4
f:0
g:1
h:1
i:0
j:0
k:1
l:2
m:1
n:0
o:3
p:0
q:0
r:2
s:1
t:1
u:2
v:0
w:1
x:0
y:1
z:0
NumberOfElementsLessThanAverage :12
BUILD SUCCESSFUL (total time: 1 second)

//PLS give a thumbs up if you find this helpful, its helps me alot, thanks.