Create 447. Number of Boomerangs

Author: stone16

447. Number of Boomerangs

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+class Solution{
+    public int numberOfBoomerangs(int[][] points) {
+        int res = 0;
+
+        Map<Integer, Integer> map = new HashMap<>();
+        for(int i=0; i<points.length; i++) {
+            for(int j=0; j<points.length; j++) {
+                if(i == j)
+                    continue;
+            
+            int d = getDistance(points[i], points[j]);                
+            map.put(d, map.getOrDefault(d, 0) + 1);
+        }
+        
+        for(int val : map.values()) {
+            res += val * (val-1);
+        }            
+        map.clear();
+    }
+    
+        return res;
+    }
+
+    private int getDistance(int[] a, int[] b) {
+        int dx = a[0] - b[0];
+        int dy = a[1] - b[1];
+    
+        return dx*dx + dy*dy;
+    }
+
+}