array - splice O(n) O(n) + sort O(nlogn) O(n)

Author: lukeist

leetcode-57-insertInterval.js

@@ -0,0 +1,61 @@
+// p: array, array;
+// r: array;
+// [[1,2],[3,5],[6,7],[8,10],[12,16]]
+// [4,8]
+// => [[1,2],[3,10],[12,16]]
+
+// interv [[1,2],[3,5],[4,8],[6,7],[8,10],[12,16]]
+// result [[1,2],[3,10],[12,16]]
+var insert = function (intervals, newInterval) {
+  // O(n) O(n) with splice()
+  let index = 0;
+  for (let i = 0; i < intervals.length; i++) {
+    if (intervals[i][0] <= newInterval[0]) index = i + 1;
+  }
+  intervals.splice(index, 0, newInterval);
+  // console.log(index, intervals);
+
+  // O(nlogn) O(n) with sort()
+  // intervals.push(newInterval);
+  // intervals.sort((a, b)=> a[0] - b[0]);
+  const result = [intervals[0]];
+  for (let i = 1; i < intervals.length; i++) {
+    const lastI = result.length - 1;
+    if (result[lastI][1] < intervals[i][0]) {
+      result.push(intervals[i]);
+    } else {
+      if (result[lastI][1] < intervals[i][1]) {
+        result[lastI][1] = intervals[i][1];
+      }
+    }
+  }
+
+  return result;
+};
+
+// 2 pointers
+
+// var insert = function(intervals, newInterval) {
+//     let start = newInterval[0];
+//     let end = newInterval[1];
+//     let res = [];
+//     let inserted = false;
+//     for (let i = 0; i < intervals.length; i++) {
+//         if (intervals[i][1] < start) {
+//             res.push(intervals[i]);
+//         } else if (intervals[i][0] > end) {
+//             if (!inserted) {
+//                 res.push([start, end]);
+//                 inserted = true;
+//             }
+//             res.push(intervals[i]);
+//         } else {
+//             start = Math.min(start, intervals[i][0]);
+//             end = Math.max(end, intervals[i][1]);
+//         }
+//     }
+//     if (!inserted) {
+//         res.push([start, end]);
+//     }
+//     return res;
+// };