Given three strings str_a, str_b, and target_str, determine if target_str can be formed by interleaving str_a and str_b. An interleaving of two strings is a sequence where the characters of both strings are merged in a way that maintains the order of characters from each string. Return True if target_str can be formed by interleaving str_a and str_b, otherwise return False.
Example 1
Input: str_a=abc, str_b=def, target_str=adbcef
Output: True
Explanation: Characters from str_a and str_b are merged in order to form target_str.
Example 2
Input: str_a=xyz, str_b=uvw, target_str=xuyvwz
Output: False
Explanation: target_str does not preserve the order of characters from str_a and str_b.
Example 3
Input: str_a=', str_b=abc, target_str=abc'
Output: True
Explanation: target_str is identical to str_b.
Constraints
Case 1
Input: str_a='aa', str_b='bb', target_str='abab'
Expected: True
Case 2
Input: str_a='abc', str_b='xyz', target_str='axbycz'
Expected: True
Case 3
Input: str_a='abc', str_b='xyz', target_str='abxcyz'
Expected: False
Case 4
Input: str_a='', str_b='', target_str=''
Expected: True
Case 5
Input: str_a='a', str_b='b', target_str='ba'
Expected: True