Exercise 07-02:
Write a program that reads two strings and generates a third with the characters common to the two strings read.
1st string: AAACTBF
2nd string: CBT
Result: CBT
The order of the characters in the result string is not important, but it must contain all the letters common to both.
Answer:
##############################################################################
# Python From Scratch
# Author: Nilo Ney Coutinho Menezes
# Editora Novatec (c) 2010-2025 - LogiKraft 2025
# Site: https://pythonfromscratch.com
# ISBN: 978-85-7522-949-1 (Paperback), 978-85-7522-950-7 (hardcover), 978-85-7522-951-4 (ebook)
#
# File: chapter 07/exercise-07-02.py.py
##############################################################################
first = input("Enter the first string: ")
second = input("Enter the second string: ")
third = ""
# For each letter in the first string
for letter in first:
# If the letter is in the second string (common to both)
# To avoid duplicates, it should not be in the third string
if letter in second and letter not in third:
third += letter
if third == "":
print("No common characters found.")
else:
print(f"Common characters: {third}")