Digital Root in Java: Explanation & Practice

Find the digital root of a number

Problem summary

Keep summing digits until you get a single digit (e.g., 9875 → 29 → 11 → 2).

Starter code

public class Main {
    public static void main(String[] args) {
        int number = 9875; // Test case 1
        
        // Calculate digital root
        // Print: Digital root: <result>
    }
}

Expected output and test cases

9875 → 29 → 11 → 2
```
Digital root: 2
```
99999 → 45 → 9
```
Digital root: 9
```
5
```
Digital root: 5
```

Hints

Outer loop: while number >= 10
Inner loop: sum all digits
Replace number with digit sum

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