Question

1. Write a Python program, in a file called concat_strings.py, that includes the following functions: orderedConcat, a recursive function that takes two alphabetically-ordered strings and merges them, leaving the letters in alphabetical order. Note that the strings may be different lengths. a main method that inputs two ordered strings and calls the orderedConcat method to return a resulting merged, ordered string. Your main method should print the two input strings and the result. Note: You may not use any of the built-in methods for string concatenation or ordering, but you may use the len() function and the slice operator (:). You may assume that the input strings are already ordered. Sample input/output: Enter the first ordered string: acdrt Enter the second ordered string: bdet First string: acdrt Second string: bdet Result: abcddertt More sample input/output: Enter the first ordered string: Deab Enter the second ordered string: BFxz First string: DEab Second string: BFxz Result: BDEFabxz

Answer 1

def concat_strings(s1, s2):
    if s1 == '':
        return s2
    elif s2 == '':
        return s1
    else:
        if s1[0] < s2[0]:
            return s1[0] + concat_strings(s1[1:], s2)
        else:
            return s2[0] + concat_strings(s1, s2[1:])


def main():
    s1 = input("Enter the first ordered string: ")
    s2 = input("Enter the second ordered string: ")
    print("First string:", s1)
    print("Second string:", s2)
    print("Result:", concat_strings(s1, s2))


main()

Enter the first ordered string: DEab Enter the second ordered string: BNXZT First string: DEab Second string: BFxz Result: BDEFabxz