solves redistribute characters to make all strings equal

Author: anishLearnsToCode

README.md

@@ -457,7 +457,7 @@
 | 1880 | [Check if Word Equals Summation of Two Words](https://leetcode.com/problems/check-if-word-equals-summation-of-two-words)                                  |                                                      [![Java](assets/java.png)](src/CheckIfWordEqualsSummationOfTwoWords.java)                                                       |                                                                                                                                   |
 | 1886 | [Determine Whether Matrix Can Be Obtained By Rotation](https://leetcode.com/problems/determine-whether-matrix-can-be-obtained-by-rotation)                |                                                  [![Java](assets/java.png)](src/DetermineWhetherMatrixCanBeObtainedByRotation.java)                                                  |                                                                                                                                   |
 | 1893 | [Check if All the Integers in a Range Are Covered](https://leetcode.com/problems/check-if-all-the-integers-in-a-range-are-covered)                        |                                                     [![Java](assets/java.png)](src/CheckIfAllTheIntegersInARangeAreCovered.java)                                                     |                                                                                                                                   |
-| 1897 | [Redistribute Characters to Make All Strings Equal](https://leetcode.com/problems/redistribute-characters-to-make-all-strings-equal)                      |                                                                                                                                                                                      |                                                                                                                                   |
+| 1897 | [Redistribute Characters to Make All Strings Equal](https://leetcode.com/problems/redistribute-characters-to-make-all-strings-equal)                      |                                                   [![Java](assets/java.png)](src/RedistributeCharactersToMakeAllStringsEqual.java)                                                   |                                                                                                                                   |
 | 1903 | [Largest Odd Number in String](https://leetcode.com/problems/largest-odd-number-in-string)                                                                |                                                                                                                                                                                      |                                                                                                                                   |
 | 1909 | [Remove One Element to Make the Array Strictly Increasing](https://leetcode.com/problems/remove-one-element-to-make-the-array-strictly-increasing)        |                                                                                                                                                                                      |                                                                                                                                   |
 | 1913 | [Maximum Product Difference Between Two Pairs](https://leetcode.com/problems/maximum-product-difference-between-two-pairs)                                |                                                                                                                                                                                      |                                                                                                                                   |

src/RedistributeCharactersToMakeAllStringsEqual.java

@@ -0,0 +1,27 @@
+// https://leetcode.com/problems/redistribute-characters-to-make-all-strings-equal
+// T: O(|words| * |word|)
+// S: O(1)
+
+import java.util.HashMap;
+import java.util.Map;
+
+public class RedistributeCharactersToMakeAllStringsEqual {
+    public boolean makeEqual(String[] words) {
+        if (words.length == 1) return true;
+        final Map<Character, Integer> frequencies = getCharacterFrequencies(words);
+        for (int frequency : frequencies.values()) {
+            if (frequency % words.length != 0) return false;
+        }
+        return true;
+    }
+
+    private Map<Character, Integer> getCharacterFrequencies(String[] words) {
+        final Map<Character, Integer> frequencies = new HashMap<>();
+        for (String word : words) {
+            for (int i = 0 ; i < word.length() ; i++) {
+                frequencies.put(word.charAt(i), frequencies.getOrDefault(word.charAt(i), 0) + 1);
+            }
+        }
+        return frequencies;
+    }
+}