Kotlin program to find the sum of natural numbers using recursion

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In this program, you will learn to use recursion in Kotlin to find the sum of natural numbers. This is done with the help of a recursive function.

Positive numbers1,2,3 ...are called natural numbers. The following program takes a positive integer from the user and calculates the sum of the given number.

You can alsoFinding the sum of natural numbers using a loop 　However, you will learn to solve this problem using recursion here.

Example: Using recursion to find the sum of natural numbers

fun　main(args:　Array<String>)　{
　　　　val　number　=　20
　　　　val　sum　=　addNumbers(number)
　　　　println("Sum　=　$sum")
}
fun　addNumbers(num:　Int):　Int　{
　　　　if　(num　!=　0)
　　　　　　　　return　num　+　addNumbers(num　-　1)
　　　　else
　　　　　　　　return　num
}

When running the program, the output is:

Sum　=　210

The numbers to be summed are stored in the variable number.

Initially, calling addNumbers() from the main() function and passing20 as the parameter.

and pass number(2) plus the result addNumbers(19) .

In the next function call from addNumbers() to addNumbers(), the following is passed:19, it is added to the result of addNumbers(18. This process continues until num equals 0.

When num equals 0, there is no recursive call, which will return the sum of integers to the main() function.

This is the equivalent Java code:Java Program Using Recursion to Find the Sum of Natural Numbers

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