Create 1207-unique-number-of-occurrences.java

Author: sujal-goswami

java/1207-unique-number-of-occurrences.java

@@ -0,0 +1,15 @@
+class Solution {
+    public boolean uniqueOccurrences(int[] arr) {
+        Map<Integer, Integer> map = new HashMap<>();
+        for(int n: arr)
+            map.put(n, map.getOrDefault(n, 0) + 1);
+
+        Set<Integer> set = new HashSet<>();
+        for(int n: map.keySet()){
+            if(set.contains(map.get(n)))
+                return false;
+            set.add(map.get(n));    
+        } 
+        return true;   
+    }
+}