Java Exercises: Convert a octal number to a decimal number
Java Basic: Exercise-25 with Solution
Write a Java program to convert a octal number to a decimal number.
Octal number: The octal numeral system is the base-8 number system, and uses the digits 0 to 7.
Decimal number: The decimal numeral system is the standard system for denoting integer and non-integer numbers. It is also called base-ten positional numeral system.
Test Data:
Input any octal number: 10
Pictorial Presentation: Octal to Decimal number

Sample Solution:
Java Code:
import java.util.Scanner;
public class Exercise25 {
public static void main(String[] args)
{
Scanner in = new Scanner(System.in);
long octal_num, decimal_num = 0;
int i = 0;
System.out.print("Input any octal number: ");
octal_num = in.nextLong();
while (octal_num != 0)
{
decimal_num = (long)(decimal_num + (octal_num % 10) * Math.pow(8, i++));
octal_num = octal_num / 10;
}
System.out.print("Equivalent decimal number: " + decimal_num+"\n");
}
}
Sample Output:
Input any octal number: 10 Equivalent decimal number: 8
Flowchart:

Java Code Editor:
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Previous: Write a Java program to convert a binary number to a Octal number.
Next: Write a Java program to convert a octal number to a binary number.
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Java: Tips of the Day
getEnumMap
Converts to enum to Map where key is the name and value is Enum itself.
public static <E extends Enum<E>> Map<String, E> getEnumMap(final Class<E> enumClass) { return Arrays.stream(enumClass.getEnumConstants()) .collect(Collectors.toMap(Enum::name, Function.identity())); }
Ref: https://bit.ly/3xXcFZt
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