Add All Elements In Array in Java

An example on adding all the elements in an array that user gives. A really simple logic involving 2 main steps.

Add all Elements in Array

import java.util.*;

class SumArray

{





 public static void main(String args[])

 {



 

 // Create a Scanner object for taking input from cmd

 Scanner s=new Scanner(System.in);



 

 // Take the no.of elements that user want to sum

 int n=s.nextInt();



 

 // Create an array of given size (n)

 int[] a=new int[n];



 

 // Initialize sum to 0

 int sum=0;



 

  // Loop till end of array

  for(int i=0;i<a.length;i++)

  {



  

  // Read int from user and store it in each element

  a[i]=s.nextInt();



  

  // Sum every element that user gives and store it in sum

  sum+=a[i];

  

  

  }

  

  

  System.out.println("The sum of all the elements is "+sum);

  

  

 }

 

 

}

Output

5

1

2

3

4

5

The sum of all the elements is 15

Tips:

You can also use n instead of a.length

sum+=a[i] is equal to sum=sum+a[i]


Similarly you can apply this logic for other data types also. If you apply for a char, a string will be resulted if you apply for a string concatenation will be done and might appear as a sentence. For other numeric data types like long,float,double etc, you'll get the sum.

Analysis

n=5: No. of elements to be added are 5

sum=0: Initially the sum of all the elements is 0.

a[i]=s.nextInt(): Initially at first i=0, afterwards i increments.

a[0]=1

0=0+1 = 1 => sum=1

a[1]=2

1=1+2 = 3 => sum=3

a[2]=3

3=3+3 = 6 => sum=6

a[3]=4

6=6+4 = 10 => sum=10

a[4]=5

10=10+5 = 15 => sum=15

End of loop. Control comes out. The value in sum (15) will be printed.