Question

Given a string of numbers, return the sum of the individual numbers recursively.

For example:
sumNumbers("10") returns 1
sumNumbers("111") returns 3
sumNumbers("259") returns 16
sumNumbers("1234") returns 10

use recursion and paste .java code below

Answer 1

To sum the digits of a string recursively in Java, the function sumNumbers is defined. It adds the numeric value of the first character to the result of a recursive call with the remaining string. The recursion ends when the string is empty.

Step-by-step explanation:

Recursion is a method of solving problems in programming where a function calls itself as a subroutine. This approach can be used to solve the problem of summing the digits of a string of numbers. Here's a Java method that uses recursion to accomplish this task:

public class Main {
public static void main(String[] args) {
System.out.println(sumNumbers("259")); // Output: 16
}

public static int sumNumbers(String str) {
if (str.isEmpty()) {
return 0;
} else {
return Integer.parseInt(str.substring(0, 1)) + sumNumbers(str.substring(1));
}
}
}

In this function, sumNumbers takes a string and adds the numeric value of the first character to the result of a recursive call where the first character is removed. The base case for the recursion is an empty string, at which point the function returns 0, ending the recursion. This approach efficiently calculates the sum of individual numbers within the string.