You are given a 0-indexed array words consisting of distinct strings.
The string words[i] can be paired with the string words[j] if:
words[i] is equal to the reversed string of words[j].0 <= i < j < words.length.Return the maximum number of pairs that can be formed from the array words.
Note that each string can belong in at most one pair.
\n\n\n
Example 1:
\n\n\nInput: words = ["cd","ac","dc","ca","zz"]\nOutput: 2\nExplanation: In this example, we can form 2 pair of strings in the following way:\n- We pair the 0th string with the 2nd string, as the reversed string of word[0] is "dc" and is equal to words[2].\n- We pair the 1st string with the 3rd string, as the reversed string of word[1] is "ca" and is equal to words[3].\nIt can be proven that 2 is the maximum number of pairs that can be formed.\n\n
Example 2:
\n\n\nInput: words = ["ab","ba","cc"]\nOutput: 1\nExplanation: In this example, we can form 1 pair of strings in the following way:\n- We pair the 0th string with the 1st string, as the reversed string of words[1] is "ab" and is equal to words[0].\nIt can be proven that 1 is the maximum number of pairs that can be formed.\n\n\n
Example 3:
\n\n\nInput: words = ["aa","ab"]\nOutput: 0\nExplanation: In this example, we are unable to form any pair of strings.\n\n\n
\n
Constraints:
\n\n1 <= words.length <= 50words[i].length == 2words consists of distinct strings.words[i] contains only lowercase English letters.Compiled with clang 11 using the latest C++ 20 standard.
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