#!/bin/bash

# Function to calculate GCD using the Euclidean algorithm
gcd() {
    a=$1
    b=$2

    while [ $b -ne 0 ]; do
        temp=$b
        b=$((a % b))
        a=$temp
    done

    echo "The GCD is: $a"
}

# Prompt the user for two numbers
echo "Please enter the first number:"
read num1

echo "Please enter the second number:"
read num2

# Check if the inputs are valid integers
if [[ $num1 =~ ^-?[0-9]+$ ]] && [[ $num2 =~ ^-?[0-9]+$ ]]; then
    # Call the function to calculate GCD
    gcd "$num1" "$num2"
else
    echo "Invalid input. Please enter valid integers."
fi