diff --git a/algorithms/src/main/java/com/baeldung/algorithms/string/EnglishAlphabetLetters.java b/algorithms/src/main/java/com/baeldung/algorithms/string/EnglishAlphabetLetters.java new file mode 100644 index 0000000000..2dd1fdcb75 --- /dev/null +++ b/algorithms/src/main/java/com/baeldung/algorithms/string/EnglishAlphabetLetters.java @@ -0,0 +1,35 @@ +package com.baeldung.algorithms.string; + +public class EnglishAlphabetLetters { + + public static boolean checkStringForAllTheLetters(String input) { + boolean[] visited = new boolean[26]; + + int index = 0; + + for (int id = 0; id < input.length(); id++) { + if ('a' <= input.charAt(id) && input.charAt(id) <= 'z') { + index = input.charAt(id) - 'a'; + } else if ('A' <= input.charAt(id) && input.charAt(id) <= 'Z') { + index = input.charAt(id) - 'A'; + } + visited[index] = true; + } + + for (int id = 0; id < 26; id++) { + if (!visited[id]) { + return false; + } + } + return true; + } + + public static boolean checkStringForAllLetterUsingStream(String input) { + long c = input.toLowerCase().chars().filter(ch -> ch >= 'a' && ch <= 'z').distinct().count(); + return c == 26; + } + + public static void main(String[] args) { + checkStringForAllLetterUsingStream("intit"); + } +} \ No newline at end of file diff --git a/algorithms/src/test/java/com/baeldung/algorithms/string/EnglishAlphabetLettersTest.java b/algorithms/src/test/java/com/baeldung/algorithms/string/EnglishAlphabetLettersTest.java new file mode 100644 index 0000000000..54335c62d2 --- /dev/null +++ b/algorithms/src/test/java/com/baeldung/algorithms/string/EnglishAlphabetLettersTest.java @@ -0,0 +1,20 @@ +package com.baeldung.algorithms.string; + +import org.junit.jupiter.api.Assertions; +import org.junit.jupiter.api.Test; + +public class EnglishAlphabetLettersTest { + + @Test + void givenString_whenContainsAllCharacter_thenTrue() { + String input = "Farmer jack realized that big yellow quilts were expensive"; + Assertions.assertTrue(EnglishAlphabetLetters.checkStringForAllTheLetters(input)); + } + + @Test + void givenString_whenContainsAllCharacter_thenUsingStreamExpectTrue() { + String input = "Farmer jack realized that big yellow quilts were expensive"; + Assertions.assertTrue(EnglishAlphabetLetters.checkStringForAllLetterUsingStream(input)); + } + +}