Calculate The Sum Up To 100 in Java

Exercise:

Write a Java Program to calculate the sum of natural numbers up to 50.

1.Compute sum using for loop.

Click Here to View the Solution!
public class SumNaturalNumbers {
 
    public static void main(String[] args) {
 
        int num = 50, sum = 0;
 
        for(int i = 1; i <= num; ++i)
        {
            sum += i;
        }
 
        System.out.println("Sum = " + sum);
    }
} 
Click Here to View the Output!
Sum = 1275
Click Here to View the Explanation!
  • This program is used for calculating the sum of all the natural numbers initialized in the program by using the for loop.
  • The natural numbers start from 1 till the given number. A given number 50 is stored in an integer variable num. Hence all the numbers starting from 1 will be added till 50.
  • A for loop is used for stating the condition expression which will loop the numbers starting from 1 and till num and keep adding numbers in the variable sum which was initially 0.
  • Finally, the sum of all the natural numbers will be printed as “Sum = 1275” for num = 50

2.Compute sum using While loop.

Click Here to View the Solution!
public class SumNaturalNumbers {
 
    public static void main(String[] args) {
 
        int num = 100, i = 1, sum = 0;
 
        while(i <= num)
        {
            sum += i;
            i++;
        }
 
        System.out.println("Sum = " + sum);
    }
} 
Click Here to View the Output!
Sum = 5050
Click Here to View the Explanation!
  • This program is used for finding the sum of natural numbers by using a while loop.
  • Initially, a number 100 is stored into the variable num which will be the number till where the addition occurs, a variable i as 1 and a variable sum as 0.
  • Like the above program using for loop, this program loops and increments the variable i, num number of times inside the body of the while loop and keeps adding its value into the variable sum.
  • Both the for loop and while loop are considered to be appropriate for performing this task however, for loop is considered a better option since it knows the number of iterations till the variable num.
  • The result is stored in the variable sum and is displayed as “Sum = 5050”.