Package g2001_2100.s2023_number_of_pairs_of_strings_with_concatenation_equal_to_target

Class Solution

java.lang.Object
g2001_2100.s2023_number_of_pairs_of_strings_with_concatenation_equal_to_target.Solution
public class Solution extends java.lang.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 Summary

    Constructors
    Constructor
    Description
    Solution()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    int
    numOfPairs(java.lang.String[] nums, java.lang.String target)
     

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Constructor Details

    • Solution

      public Solution()

  • Method Details

    • numOfPairs

      public int numOfPairs(java.lang.String[] nums, java.lang.String target)