Biased Binary Search; Arrays.stream(int[]).boxed().collect(Collectors.toList()) to convert array to list

Author: GuanhuiGuan

Find K Closest Elements.java

@@ -0,0 +1,16 @@
+class Solution {
+    public List<Integer> findClosestElements(int[] arr, int k, int x) {
+        if(k > arr.length) return null;
+        int n = arr.length;
+        int lo = 0, hi = n - k;
+        
+        // binary search find the left starting point
+        while(lo < hi) {
+            int m = lo + (hi - lo) / 2;
+            if(x - arr[m] > arr[m+k] - x) lo = m + 1;
+            else hi = m;
+        }
+        int[] res = Arrays.copyOfRange(arr, lo, lo + k);
+        return Arrays.stream(res).boxed().collect(Collectors.toList());
+    }
+}