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Ruby program to get the GCD and LCM using gcdlcm() library function

Last Updated : December 15, 2025

Problem Solution

In this program, we will read two integer variables from the user. Then we will get the Greatest Common Divisor and Lowest Common Multiple using the gcdlcm() function.

Program/Source Code

The source code to get the GCD and LCM using the gcdlcm() library function is given below. The given program is compiled and executed successfully.

# Ruby program to get the GCD and LCM using 
# the gcdlcm() library function

print "Enter number1: ";
num1 = gets.chomp.to_i;  

print "Enter number2: ";
num2 = gets.chomp.to_i;  

gcd,lcm = num1.gcdlcm(num2);

print "Greatest Common Divisor: ",gcd,"\n";
print "Lowest Common Multiple:  ",lcm,"\n";

Output

Enter number1: 21
Enter number2: 14
Greatest Common Divisor: 7
Lowest Common Multiple:  42

Explanation

In the above program, we read two integer variables from the user using gets.chomp.to_i. Then we got the Greatest Common Divisor and  Lowest Common Multiple using library function the gcdlcm() and assign the result to the gcd ,lcd variables. After that, we printed the result.

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