Given a set of strings. Find the length of smallest string which
has all the strings in the set as substring
1) 1 <= Number of strings <= 18
2) Length of any string in the set will not exceed 100.
Input: [“abcd”, “cdef”, “fgh”, “de”]
Output: 8 (Shortest string: “abcdefgh”)
NOTE: You only need to implement the given function. Do not read input, instead use the arguments to the function. Do not print the output, instead return values as specified. Still have a doubt? Checkout Sample Codes for more details.