Non-Repeating Element

Sushma-Kumari131 · web-flow · commit 67452170cc95 · 2020-10-06T20:33:10.000+05:30
Java program to find first non-repeating  element.
diff --git a/Non-Repeating Element b/Non-Repeating Element
@@ -0,0 +1,34 @@
+import java.util.*; 
+  
+class GFG { 
+  
+    static void firstNonRepeating(int arr[], int n) 
+    { 
+        // Insert all array elements in hash 
+        // table 
+        Map<Integer, Integer> m = new HashMap<>(); 
+        for (int i = 0; i < n; i++) { 
+            if (m.containsKey(arr[i])) { 
+                m.put(arr[i], m.get(arr[i]) + 1); 
+            } 
+            else { 
+                m.put(arr[i], 1); 
+            } 
+        } 
+  
+        // Traverse through map only and 
+        // using for-each loop for iteration over Map.entrySet() 
+        for (Map.Entry<Integer, Integer> x : m.entrySet()) 
+            if (x.getValue() == 1) 
+                System.out.print(x.getKey() + " "); 
+    } 
+  
+    // Driver code 
+    public static void main(String[] args) 
+    { 
+        int arr[] = { 9, 4, 9, 6, 7, 4 }; 
+        int n = arr.length; 
+        firstNonRepeating(arr, n); 
+    } 
+} 
+  
