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Ruby program to count the digits of a given number using recursion

Last Updated : December 15, 2025

Problem Solution

In this program, we will read an integer number from the user and count the digits of the input number using recursion.

Program/Source Code

The source code to count the digits of a given number using recursion is given below. The given program is compiled and executed successfully.

# Ruby program to count the digits 
# of given number using recursion

def CountDigits(num,count)
	if num > 0 
		CountDigits(num / 10,count+1);
	else
	    return count;    
	end
end

print "Enter number: ";
number = gets.chomp.to_i;  

result = CountDigits(number, 0);
print "Total digits are: ",result;

Output

Enter number: 4326
Total digits are: 4

Explanation

In the above program, we read an integer number from the user. Then we count the digits of the input number using the recursive function CountDigits(). Then we printed the result.

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