Addition of hidden numbers 1 (with.Java)

This is an article about the “Addition of hidden numbers 1” problem.

As I solve coding test problems, I look back on the problems I solved and look into different solution methods to learn more.

Let’s look at the problem first.

problem

The string my_string is given as a parameter.

Complete the solution function to return the sum of all natural numbers in my_string.

Restrictions

• 1 ≤ length of my_string ≤ 1,000
• my_string consists only of lowercase letters, uppercase letters, and one-digit natural numbers.

Input/Output Example

My solution to the problem

class Solution {
     public int solution(String my_string) {
         int answer = 0;
         for (char ch : my_string.toCharArray()) {
             if (Character.isDigit(ch)) {
                 answer += Character.getNumericValue(ch);
             }
         }
         return answer;
     }
}

Solution explanation

• solution(String my_string): Extracts a number from the given string my_string and returns the result of adding the extracted numbers.
• int answer: Variable to store the final result.
• While iterating through the string, use Character.isDigit(ch) to check whether each character is a number. If it is a number, use Character.getNumericValue(ch) to accumulate and add the numbers.
• Returns the final added value.

Code Advantages

• Easy to add numbers: The process of extracting numbers from each letter and adding them is simple and intuitive.

Code Disadvantages

• Number range limitation: The code extracts only numbers from 0 to 9 from the string and adds them. If you need a different number range, you will need to modify your code.