solves fidn the town judge

Author: anishLearnsToCode

README.md

@@ -267,7 +267,7 @@
 | 985 | [Sum of Even Numbers after Queries](https://leetcode.com/problems/sum-of-even-numbers-after-queries) | |
 | 989 | [Add to Array Form of Integer](https://leetcode.com/problems/add-to-array-form-of-integer) | [![Java](assets/java.png)](src/AddToArrayFormOfInteger.java) |
 | 993 | [Cousins in Binary Tree](https://leetcode.com/problems/cousins-in-binary-tree) | [![Java](assets/java.png)](src/CousinsInBinaryTree.java) |
-| 997 | [Find the Town Judge](https://leetcode.com/problems/find-the-town-judge) | |
+| 997 | [Find the Town Judge](https://leetcode.com/problems/find-the-town-judge) | [![Java](assets/java.png)](src/FindTheTownJudge.java) |
 | 999 | [Available Captures for Rook](https://leetcode.com/problems/available-captures-for-rook) | |
 | 1002 | [Find Common Characters](https://leetcode.com/problems/find-common-characters) | |
 | 1005 | [Maximize Sum of Array After K Negations](https://leetcode.com/problems/maximize-sum-of-array-after-k-negations) | |

src/FindTheTownJudge.java

@@ -0,0 +1,18 @@
+import java.util.HashMap;
+import java.util.Map;
+
+public class FindTheTownJudge {
+    public int findJudge(int n, int[][] trust) {
+        Map<Integer, Integer> inDegreeTrust = new HashMap<>();
+        Map<Integer, Integer> outDegreeTrust = new HashMap<>();
+        for (int[] person : trust) {
+            inDegreeTrust.put(person[1], inDegreeTrust.getOrDefault(person[1], 0) + 1);
+            outDegreeTrust.put(person[0], inDegreeTrust.getOrDefault(person[0], 0) + 1);
+        }
+        for (int i = 1 ; i <= n ; i++) {
+            if (outDegreeTrust.getOrDefault(i, 0) == 0 && inDegreeTrust.getOrDefault(i, 0) == n - 1)
+                return i;
+        }
+        return -1;
+    }
+}