Package g2701_2800.s2744_find_maximum_number_of_string_pairs

Class Solution

  • public class Solution
extends Object
    2744 - Find Maximum Number of String Pairs.

    Easy

    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:

    • The string 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.

    Example 1:

    Input: words = [“cd”,“ac”,“dc”,“ca”,“zz”]

    Output: 2

    Explanation: In this example, we can form 2 pair of strings in the following way:

    • We pair the 0th string with the 2nd string, as the reversed string of word[0] is “dc” and is equal to words[2].
    • We pair the 1st string with the 3rd string, as the reversed string of word[1] is “ca” and is equal to words[3].

    It can be proven that 2 is the maximum number of pairs that can be formed.

    Example 2:

    Input: words = [“ab”,“ba”,“cc”]

    Output: 1

    Explanation: In this example, we can form 1 pair of strings in the following way:

    • We pair the 0th string with the 1st string, as the reversed string of words[1] is “ab” and is equal to words[0].

    It can be proven that 1 is the maximum number of pairs that can be formed.

    Example 3:

    Input: words = [“aa”,“ab”]

    Output: 0

    Explanation: In this example, we are unable to form any pair of strings.

    Constraints:

    • 1 <= words.length <= 50
    • words[i].length == 2
    • words consists of distinct strings.
    • words[i] contains only lowercase English letters.

    • Constructor Detail

      • Solution

        public Solution()

    • Method Detail

      • maximumNumberOfStringPairs

        public int maximumNumberOfStringPairs​(String[] words)