soles finding3digit evennumbers

Author: anishLearnsToCode

README.md

@@ -496,6 +496,6 @@
 | 2078 | [Two Furthest Houses With Different Colors](https://leetcode.com/problems/two-furthest-houses-with-different-colors)                                      |                                                      [![Java](assets/java.png)](src/TwoFurthestHousesWithDifferentColors.java)                                                       |                                                                                                                                   |
 | 2085 | [Count Common Words With One Occurrence](https://leetcode.com/problems/count-common-words-with-one-occurrence)                                            |                                                        [![Java](assets/java.png)](src/CountCommonWordsWithOneOccurrence.java)                                                        |                                                                                                                                   |
 | 2089 | [Find Target Indices After Sorting Array](https://leetcode.com/problems/find-target-indices-after-sorting-array)                                          |                                                       [![Java](assets/java.png)](src/FindTargetIndicesAfterSortingArray.java)                                                        |                                                                                                                                   |
-| 2094 | [Finding 3-Digit Even Numbers](https://leetcode.com/problems/finding-3-digit-even-numbers)                                                                |                                                                                                                                                                                      |                                                                                                                                   |
+| 2094 | [Finding 3-Digit Even Numbers](https://leetcode.com/problems/finding-3-digit-even-numbers)                                                                |                                                            [![Java](assets/java.png)](src/Finding3DigitEvenNumbers.java)                                                             |                                                                                                                                   |
 | 2099 | [Find Subsequence of Length K With the Largest Sum](https://leetcode.com/problems/find-subsequence-of-length-k-with-the-largest-sum)                      |                                                                                                                                                                                      |                                                                                                                                   |
 | 2103 | [Rings and Rods](https://leetcode.com/problems/rings-and-rods)                                                                                            |                                                                                                                                                                                      |                                                                                                                                   |

src/Finding3DigitEvenNumbers.java

@@ -0,0 +1,57 @@
+// https://leetcode.com/problems/finding-3-digit-even-numbers
+// T: O(N)
+// S: O(N)
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+public class Finding3DigitEvenNumbers {
+    public int[] findEvenNumbers(int[] digits) {
+        final Map<Integer, Integer> frequencies = getFrequency(digits);
+        final List<Integer> numbers = new ArrayList<>();
+        for (int number = 100 ; number <= 999 ; number += 2) {
+            if (canBeFormed(number, frequencies)) {
+                numbers.add(number);
+            }
+        }
+        return toArray(numbers);
+    }
+
+    private boolean canBeFormed(int number, Map<Integer, Integer> digits) {
+        final Map<Integer, Integer> numberDigits = getFrequency(number);
+        for (Map.Entry<Integer, Integer> entry : numberDigits.entrySet()) {
+            if (digits.getOrDefault(entry.getKey(), 0) < entry.getValue()) {
+                return false;
+            }
+        }
+        return true;
+    }
+
+    private int[] toArray(List<Integer> list) {
+        final int[] array = new int[list.size()];
+        for (int i = 0 ; i < list.size() ; i++) {
+            array[i] = list.get(i);
+        }
+        return array;
+    }
+
+    private Map<Integer, Integer> getFrequency(int[] array) {
+        final Map<Integer, Integer> frequency = new HashMap<>();
+        for (int element : array) {
+            frequency.put(element, frequency.getOrDefault(element, 0) + 1);
+        }
+        return frequency;
+    }
+
+    private Map<Integer, Integer> getFrequency(int number) {
+        final Map<Integer, Integer> frequency = new HashMap<>();
+        while (number > 0) {
+            int digit = number % 10;
+            frequency.put(digit, frequency.getOrDefault(digit, 0) + 1);
+            number /= 10;
+        }
+        return frequency;
+    }
+}