Add Modified Binary Search/719_Find_K-th_Smallest_Pair_Distance.java

Author: seanprashad

Modified Binary Search/719_Find_K-th_Smallest_Pair_Distance.java

@@ -0,0 +1,34 @@
+class Solution {
+    public int smallestDistancePair(int[] nums, int k) {
+        Arrays.sort(nums);
+        int low = 0, high = nums[nums.length - 1] - nums[0];
+
+        while (low < high) {
+            int mid = low + (high - low) / 2;
+
+            int count = smallestDistancePairHelper(nums, mid);
+            if (count < k) {
+                low = mid + 1;
+            } else {
+                high = mid;
+            }
+        }
+
+        return low;
+    }
+
+    private int smallestDistancePairHelper(int[] nums, int maxValue) {
+        int left = 0, right = 0, count = 0;
+
+        while (right < nums.length) {
+            while (left < right && nums[right] - nums[left] > maxValue) {
+                ++left;
+            }
+
+            count += right - left;
+            ++right;
+        }
+
+        return count;
+    }
+}