Insert Interval done

Author: rampatra

src/main/java/com/leetcode/arrays/InsertInterval.java

@@ -0,0 +1,78 @@
+package com.leetcode.arrays;
+
+import java.util.Arrays;
+
+/**
+ * Level: Hard
+ * Problem Link: https://leetcode.com/problems/insert-interval/
+ * Problem Description:
+ * Given a set of non-overlapping intervals, insert a new interval into the intervals (merge if necessary).
+ * <p>
+ * You may assume that the intervals were initially sorted according to their start times.
+ * <p>
+ * Example 1:
+ * Input: intervals = [[1,3],[6,9]], newInterval = [2,5]
+ * Output: [[1,5],[6,9]]
+ * <p>
+ * Example 2:
+ * Input: intervals = [[1,2],[3,5],[6,7],[8,10],[12,16]], newInterval = [4,8]
+ * Output: [[1,2],[3,10],[12,16]]
+ * Explanation: Because the new interval [4,8] overlaps with [3,5],[6,7],[8,10].
+ * <p>
+ * Companies: LinkedIn
+ * Related: {@link MergeIntervals}.
+ *
+ * @author rampatra
+ * @since 2019-07-23
+ */
+public class InsertInterval {
+
+    /**
+     * Time Complexity: O(n)
+     * Space Complexity: O(n)
+     * Runtime: <a href="https://leetcode.com/submissions/detail/245767085/">2 ms</a>.
+     *
+     * @param intervals
+     * @param newInterval
+     * @return
+     */
+    public static int[][] insert(int[][] intervals, int[] newInterval) {
+        if (intervals.length == 0 && newInterval.length == 0) {
+            return new int[][]{};
+        } else if (intervals.length == 0) {
+            return new int[][]{newInterval};
+        }
+
+        int[][] mergedIntervals = new int[intervals.length + 1][2];
+        int j = 0;
+
+        for (int i = 0; i < intervals.length; i++) {
+            if (newInterval == null || newInterval[0] > intervals[i][1]) { // newInterval is after the ith interval
+                mergedIntervals[j++] = intervals[i];
+            } else if (newInterval[1] < intervals[i][0]) { // newInterval is before the ith interval
+                mergedIntervals[j++] = newInterval;
+                mergedIntervals[j++] = intervals[i];
+                newInterval = null;
+            } else { // if overlapping
+                newInterval[0] = Math.min(newInterval[0], intervals[i][0]);
+                newInterval[1] = Math.max(newInterval[1], intervals[i][1]);
+            }
+        }
+
+        if (newInterval != null) {
+            mergedIntervals[j++] = newInterval;
+        }
+
+        return Arrays.copyOfRange(mergedIntervals, 0, j);
+    }
+
+    public static void main(String[] args) {
+        System.out.println(Arrays.deepToString(insert(new int[][]{}, new int[]{})));
+        System.out.println(Arrays.deepToString(insert(new int[][]{}, new int[]{5, 7})));
+        System.out.println(Arrays.deepToString(insert(new int[][]{{1, 5}}, new int[]{0, 0})));
+        System.out.println(Arrays.deepToString(insert(new int[][]{{1, 5}}, new int[]{2, 3})));
+        System.out.println(Arrays.deepToString(insert(new int[][]{{2, 5}, {6, 7}, {8, 9}}, new int[]{0, 1})));
+        System.out.println(Arrays.deepToString(insert(new int[][]{{1, 3}, {6, 9}}, new int[]{2, 5})));
+        System.out.println(Arrays.deepToString(insert(new int[][]{{1, 2}, {3, 5}, {6, 7}, {8, 10}, {12, 16}}, new int[]{4, 8})));
+    }
+}

src/main/java/com/leetcode/arrays/MergeIntervals.java

@@ -19,6 +19,9 @@
  * Input: [[1,4],[4,5]]
  * Output: [[1,5]]
  * Explanation: Intervals [1,4] and [4,5] are considered overlapping.
+ * <p>
+ * Companies: LinkedIn
+ * Related: {@link InsertInterval}.
  *
  * @author rampatra
  * @since 2019-07-22