BlueJ Programs on in Displaying Average of Array Elements

We will go through few program on array in java. I think it would help students of ICSE and ISC in their computer application paper.

Suppose we want to enter ages of 'n' number of persons in an array. Here the user will decide the array size.

import java.io.*;
class Arr
{
int arr [ ], n;
BufferedReader br=new BufferedReader(new InputStreamReader ( System.in));
void takeAge() throws IOException
{
System.out.println(“ How many Persons:”);
n=Integer.parseInt(br.readLine());
arr=new int[n];
for (i=0;i < n;i++)
{
System.out.println(“ How many persons ");
arr[i]=Integer.parseInt(br.readLine());
}
System.out.println(“Entered Ages are as follows “);
for (i=0;i < n;i++)
{
System.out.println(“ “+ arr[i]);
}
}
}

From the above BlueJ program on array, it is clear that the user decides the size of the array and it is possible as java array is dynamic. But consider another case. Suppose the user don’t know how many values he has to store at the start of the program. As he continues entering values, at some point he has to stop.

In such case we will create an array with maximum size. For example if we want to ages of students of a particular class of a school, the number of students in a class can’t be more than 500 in any case. So user can go on entering values without any risk.


import java.io.*;
class Arr
{
int arr [ ], [500], n;
BufferedReader br=new BufferedReader(new InputStreamReader ( System.in));
arr=new int[500];
char ch=’y’;
void takeAge() throws IOException
{
while (ch !=’n’)
{
System.out.println(“ Enter age:”)
arr[n++]=Integer.parseInt(br.readLine());
System.out.println(“Any more student (y/n):”);
ch=(char)br.readLine();
}
System.out.println(“Entered Ages are “);
for (i=0;i < n;i++)
{
System.out.println(“ “+ arr[i]);
}
}
}

Here is another program . Take 'n' number of integer values from the user; display the value of 'n' and the average of the numbers.

import java.io.*;
class Arr
{
int number [];
char ch='y';
number=new int[500];
void takedata() throws IOException
{
int i=0, sum=0;

while (ch!='n')
{
System.out.println ("Enter the number:");
number[i++]=Integer.parseInt(br.readLine());
sum=sum+number [i];

System.out.println ("Any more? (y/n)");
ch=(char)br.readLine();
}
System.out.println ("The total is :”+ sum);
System.out.println ("Average is :"+(float) sum/counter);
}
}

Related Post: BlueJ Programs on Numeric Array