Create 1964-find-the-longest-valid-obstacle-course-at-each-position.kt

Author: a93a

Diff for: kotlin/1964-find-the-longest-valid-obstacle-course-at-each-position.kt

@@ -0,0 +1,27 @@
+class Solution {
+    fun longestObstacleCourseAtEachPosition(obstacles: IntArray): IntArray {
+        val dp = IntArray(obstacles.size) { Integer.MAX_VALUE }
+        val res = IntArray(obstacles.size)
+
+        fun binarySearch(n: Int): Int {
+            var l = 0
+            var r = dp.lastIndex
+
+            while (l < r) {
+                val m = l + (r - l) / 2
+                if (n >= dp[m]) l = m + 1
+                else r = m
+            }
+
+            return l
+        }
+
+        for ((i, n) in obstacles.withIndex()) {
+            val insert = binarySearch(n)
+            res[i] = insert + 1
+            dp[insert] = n
+        }
+
+        return res
+    }
+}