Package g1601_1700.s1638_count_substrings_that_differ_by_one_character

Class Solution

  • public class Solution
extends Object
    1638 - Count Substrings That Differ by One Character.

    Medium

    Given two strings s and t, find the number of ways you can choose a non-empty substring of s and replace a single character by a different character such that the resulting substring is a substring of t. In other words, find the number of substrings in s that differ from some substring in t by exactly one character.

    For example, the underlined substrings in "computer" and "computation" only differ by the 'e'/'a', so this is a valid way.

    Return the number of substrings that satisfy the condition above.

    A substring is a contiguous sequence of characters within a string.

    Example 1:

    Input: s = “aba”, t = “baba”

    Output: 6

    Explanation: The following are the pairs of substrings from s and t that differ by exactly 1 character:

    (“aba”, “baba”)

    (“aba”, “baba”)

    (“aba”, “baba”)

    (“aba”, “baba”)

    (“aba”, “baba”)

    (“aba”, “baba”)

    The underlined portions are the substrings that are chosen from s and t.

    Example 2:

    Input: s = “ab”, t = “bb”

    Output: 3

    Explanation: The following are the pairs of substrings from s and t that differ by 1 character:

    (“ab”, “bb”)

    (“ab”, “bb”)

    (“ab”, “bb”)

    The underlined portions are the substrings that are chosen from s and t.

    Constraints:

    • 1 <= s.length, t.length <= 100
    • s and t consist of lowercase English letters only.

    • Constructor Detail

      • Solution

        public Solution()

    • Method Detail

      • countSubstrings

        public int countSubstrings​(String s,
                           String t)