solves find words that can be formed by characters

Author: anishLearnsToCode

README.md

@@ -1,7 +1,7 @@
 # LeetCode Algorithms
 
-![problems-solved](https://img.shields.io/badge/Problems%20Solved-231/2081-1f425f.svg)
-![problems-solved-java](https://img.shields.io/badge/Java-231/2081-1abc9c.svg)
+![problems-solved](https://img.shields.io/badge/Problems%20Solved-248/2081-1f425f.svg)
+![problems-solved-java](https://img.shields.io/badge/Java-248/2081-1abc9c.svg)
 ![problems-solved-python](https://img.shields.io/badge/Python-186/2081-1abc9c.svg)
 [![PRs Welcome](https://img.shields.io/badge/PRs-welcome-brightgreen.svg)](CONTRIBUTING.md)
 [![cp](https://img.shields.io/badge/also%20see-Competitve%20Programming-1f72ff.svg)](https://github.com/anishLearnsToCode/competitive-programming)
@@ -307,7 +307,7 @@
 | 1150 | [Check if Number is Majority Element in Sorted Array](https://leetcode.com/problems/check-if-a-number-is-majority-element-in-a-sorted-array)         |                                                                                                                                                                             |                                                                                                                                   |
 | 1154 | [Day of The Year](https://leetcode.com/problems/day-of-the-year)                                                                                     |                                                              [![Java](assets/java.png)](src/DayOfTheYear.java)                                                              |                                                                                                                                   |
 | 1160 | [Find Words That Can Be Formed By Characters](https://leetcode.com/problems/find-words-that-can-be-formed-by-characters)                             |                                                                                                                                                                             |                                                                                                                                   |
-| 1165 | [Single Row Keyboard](https://leetcode.com/problems/single-row-keyboard)                                                                             |                                                                                                                                                                             |                                                                                                                                   |
+| 1165 | [Single Row Keyboard](https://leetcode.com/problems/single-row-keyboard)                                                                             |                                                  [![Java](assets/java.png)](src/FindWordsThatCanBeFormedByCharacters.java)                                                  |                                                                                                                                   |
 | 1170 | [Compare Strings By Frequency of the Smallest Character](https://leetcode.com/problems/compare-strings-by-frequency-of-the-smallest-character)       |                                                                                                                                                                             |                                                                                                                                   |
 | 1175 | [Prime Arrangements](https://leetcode.com/problems/prime-arrangements)                                                                               |                                                                                                                                                                             |                                                                                                                                   |
 | 1176 | [Diet Plan Performance](https://leetcode.com/problems/diet-plan-performance)                                                                         |                                                                                                                                                                             |                                                                                                                                   |

src/FindWordsThatCanBeFormedByCharacters.java

@@ -0,0 +1,32 @@
+import java.util.HashMap;
+import java.util.Map;
+
+public class FindWordsThatCanBeFormedByCharacters {
+    public int countCharacters(String[] words, String chars) {
+        final Map<Character, Integer> characterFrequencies = getCharFrequencies(chars);
+        int result = 0;
+        for (String word : words) {
+            if (word.length() > chars.length()) continue;
+            Map<Character, Integer> wordCharFrequencies = getCharFrequencies(word);
+            if (canBeFormedBy(wordCharFrequencies, characterFrequencies)) {
+                result += word.length();
+            }
+        }
+        return result;
+    }
+
+    private Map<Character, Integer> getCharFrequencies(String string) {
+        Map<Character, Integer> frequencies = new HashMap<>();
+        for (int index = 0 ; index < string.length() ; index++) {
+            frequencies.put(string.charAt(index), frequencies.getOrDefault(string.charAt(index), 0) + 1);
+        }
+        return frequencies;
+    }
+
+    private boolean canBeFormedBy(Map<Character, Integer> frequencies1, Map<Character, Integer> frequencies2) {
+        for (Map.Entry<Character, Integer> entry : frequencies1.entrySet()) {
+            if (frequencies2.getOrDefault(entry.getKey(), 0) < entry.getValue()) return false;
+        }
+        return true;
+    }
+}