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Ruby program to find the LCM of two given numbers using recursion

Last Updated : December 15, 2025

Problem Solution

In this program, we will read two integer numbers from the user and find the LCM of input numbers using recursion.

Program/Source Code

The source code to find the LCM of two given numbers using recursion is given below. The given program is compiled and executed successfully.

# Ruby program to find the LCM of 
# two given numbers using recursion

def LCM(a, b, res)
    if (res % a == 0 && res % b == 0)
        return res;
    else
        LCM(a, b,res + 1);
    end
end

print "Enter number1: ";
number1 = gets.chomp.to_i;  

print "Enter number2: ";
number2 = gets.chomp.to_i;  

result = LCM(number1, number2,1);

print "LCM is: ",result;

Output

Enter number1: 45
Enter number2: 75
LCM is: 225

Explanation

In the above program, we read two integer numbers from the user. Then we found the LCM of input numbers using recursive function LCM(). Then we printed the result.

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