String Chains:

 Given an array of words representing your dictionary, you test each word to see if it can be made into another word in the dictionary. This will be done by removing characters one at a time. Each word represents its own first element of its string chain, so start with a string chain length of 1. Each time you remove a character, increment your string chain by 1. In order to remove a character, the resulting word must be in your original dictionary. Your goal is to determine the longest string chain achievable for a given dictionary. For example, given a dictionary [a, and, an, bear), the word and could be reduced to an and then to a. The single character a cannot be reduced any further as the null string is not in the dictionary. This would be the longest string chain, having a length 3. The word bear cannot be reduced at all. Function Description Complete the function longestChain in the editor below. The function must return a single integer representing the length of the longest string chain. longestChain has the following parameter(s): words[words[0]....Words[n-1]]: an array of strings to test 

Constraints

 • 1<=n<= 50000 

• 1 <= words[i]  <= 60, where 0 <= i < n

 • Each words[i] is composed of lowercase letters in ascii[a-z]

. Input Format for Custom Testing 

Sample Case 0:

 Sample Input 0:

4

 ba bca bda bdca 

Sample Output 0:

4