Untitled

#!/bin/bash

# Define a function to check if a string is a number
is_number() {
  # Use a regular expression to match only digits
  if [[ $1 =~ ^[0-9]+$ ]]; then
    return 0 # True
  else
    return 1 # False
  fi
}

# Ask the user for a number
read -p "Enter a number: " input

# Loop until the user enters a valid number
while ! is_number "$input"; do
  echo "That's not a number. Try again."
  read -p "Enter a number: " input
done

# Echo the user's input
echo "You entered: $input"