Package g3101_3200.s3121_count_the_number_of_special_characters_ii

Class Solution

  • All Implemented Interfaces:
    
public final class Solution

    3121 - Count the Number of Special Characters II.

    Medium

    You are given a string word. A letter c is called special if it appears both in lowercase and uppercase in word, and every lowercase occurrence of c appears before the first uppercase occurrence of c.

    Return the number of special letters in word.

    Example 1:

    Input: word = "aaAbcBC"

    Output: 3

    Explanation:

    The special characters are 'a', 'b', and 'c'.

    Example 2:

    Input: word = "abc"

    Output: 0

    Explanation:

    There are no special characters in word.

    Example 3:

    Input: word = "AbBCab"

    Output: 0

    Explanation:

    There are no special characters in word.

    Constraints:

    • <code>1 <= word.length <= 2 * 10<sup>5</sup></code>

    • word consists of only lowercase and uppercase English letters.

    • Nested Class Summary

      Nested Classes 
      Modifier and Type Class Description

    • Field Summary

      Fields 
      Modifier and Type Field Description

    • Constructor Summary

      Constructors 
      Constructor Description
      Solution()

    • Enum Constant Summary

      Enum Constants 
      Enum Constant Description

    • Method Summary

      Modifier and Type Method Description
      final Integer numberOfSpecialChars(String word)

      • Methods inherited from class java.lang.Object

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