Class Solution


  • public class Solution
    extends Object
    2023 - Number of Pairs of Strings With Concatenation Equal to Target.

    Medium

    Given an array of digit strings nums and a digit string target, return the number of pairs of indices (i, j) (where i != j) such that the concatenation of nums[i] + nums[j] equals target.

    Example 1:

    Input: nums = [“777”,“7”,“77”,“77”], target = “7777”

    Output: 4

    Explanation: Valid pairs are:

    • (0, 1): “777” + “7”

    • (1, 0): “7” + “777”

    • (2, 3): “77” + “77”

    • (3, 2): “77” + “77”

    Example 2:

    Input: nums = [“123”,“4”,“12”,“34”], target = “1234”

    Output: 2

    Explanation: Valid pairs are:

    • (0, 1): “123” + “4”

    • (2, 3): “12” + “34”

    Example 3:

    Input: nums = [“1”,“1”,“1”], target = “11”

    Output: 6

    Explanation: Valid pairs are:

    • (0, 1): “1” + “1”

    • (1, 0): “1” + “1”

    • (0, 2): “1” + “1”

    • (2, 0): “1” + “1”

    • (1, 2): “1” + “1”

    • (2, 1): “1” + “1”

    Constraints:

    • 2 <= nums.length <= 100
    • 1 <= nums[i].length <= 100
    • 2 <= target.length <= 100
    • nums[i] and target consist of digits.
    • nums[i] and target do not have leading zeros.
    • Constructor Detail

      • Solution

        public Solution()
    • Method Detail

      • numOfPairs

        public int numOfPairs​(String[] nums,
                              String target)