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Java Math Exercises: Reverse an integer number

Java Math Exercises: Exercise-6 with Solution

Write a Java program to reverse an integer number.

Sample Solution:

Java Code:

public class Example6 {
   public static void main(String[] args) {
	int num =1287;   
	int is_positive = 1;
        if (num < 0) {
            is_positive = -1;
            num = -1 * num;
        }
        int sum  = 0;
        while (num > 0) {
            int r = num % 10;
            
            int maxDiff = Integer.MAX_VALUE - sum * 10;
            if (sum > Integer.MAX_VALUE / 10 || r > maxDiff) 
				System.out.println("Wrong number");;
            
            sum = sum * 10 + r;
            num /= 10;
        }
        System.out.println(is_positive * sum);
   }
}

Sample Output:

7821

Flowchart:

Flowchart: Reverse an integer number.

Java Code Editor:

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Previous: Write a Java program to count the absolute distinct value in an array.
Next: Write a Java program to convert Roman number to an integer number.

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Java: Tips of the Day

Simple way to repeat a string:

String::repeat

". ".repeat(7)  // Seven period-with-space pairs: . . . . . . .

New in Java 11 is the method String::repeat that does exactly what you asked for:

String str = "abc";
String repeated = str.repeat(3);
repeated.equals("abcabcabc");

Ref: https://bit.ly/3bNqfWN