solves #2347: Best Poker Hand in jav a

Author: anishLearnsToCode

README.md

@@ -752,7 +752,7 @@
 | 2335 | [Minimum Amount of Time to Fill Cups](https://leetcode.com/problems/minimum-amount-of-time-to-fill-cups)                                                               |                                                                                [![Java](assets/java.png)](src/MinimumAmountOfTimeToFillCups.java)                                                                                |                                                                                                                                   |
 | 2439 | [Minimize Maximum of Array](https://leetcode.com/problems/minimize-maximum-of-array)                                                                                   |                                                                               [![Python](assets/python.png)](python/minimize_maximum_of_array.py)                                                                                |                                                                                                                                   |
 | 2341 | [Maximum Number of Pairs in Array](https://leetcode.com/problems/maximum-number-of-pairs-in-array)                                                                     |                                                                                 [![Java](assets/java.png)](src/MaximumNumberOfPairsInArray.java)                                                                                 |                                                                                                                                   |
-| 2347 | [Best Poker Hand](https://leetcode.com/problems/best-poker-hand)                                                                                                       |                                                                                                                                                                                                                                  |                                                                                                                                   |
+| 2347 | [Best Poker Hand](https://leetcode.com/problems/best-poker-hand)                                                                                                       |                                                                                        [![Java](assets/java.png)](src/BestPokerHand.java)                                                                                        |                                                                                                                                   |
 | 2348 | [Number of Zero-Filled Subarrays](https://leetcode.com/problems/number-of-zero-filled-subarrays)                                                                       |                                                                            [![Python](assets/python.png)](python/number_of_zero_filled_subarrays.py)                                                                             |                                                                                                                                   |
 | 2351 | [First Letter to Appear Twice](https://leetcode.com/problems/first-letter-to-appear-twice)                                                                             |                                                                                                                                                                                                                                  |                                                                                                                                   |
 | 2357 | [Make Array Zero by Subtracting Equal Amounts](https://leetcode.com/problems/make-array-zero-by-subtracting-equal-amounts)                                             |                                                                                                                                                                                                                                  |                                                                                                                                   |

src/BestPokerHand.java

@@ -0,0 +1,42 @@
+// https://leetcode.com/problems/best-poker-hand
+// T: O(1)
+// S: O(1)
+
+import java.util.HashMap;
+import java.util.Map;
+
+public class BestPokerHand {
+    public String bestHand(int[] ranks, char[] suits) {
+        if (sameSuit(suits)) {
+            return "Flush";
+        }
+
+        final Map<Integer, Integer> frequencies = getFrequencies(ranks);
+        final int maxFrequency = frequencies.values().stream().max(Integer::compare).get();
+
+        if (maxFrequency >= 3) {
+            return "Three of a Kind";
+        }
+        if (maxFrequency == 2) {
+            return "Pair";
+        }
+
+        return "High Card";
+    }
+
+    private Map<Integer, Integer> getFrequencies(int[] ranks) {
+        final Map<Integer, Integer> frequencies = new HashMap<>();
+        for (int rank : ranks) {
+            frequencies.put(rank, frequencies.getOrDefault(rank, 0) + 1);
+        }
+        return frequencies;
+    }
+
+    private boolean sameSuit(char[] suits) {
+        char first = suits[0];
+        for (char suit : suits) {
+            if (suit != first) return false;
+        }
+        return true;
+    }
+}