Create 1235-maximum-profit-in-job-scheduling.java

Author: sujal-goswami

java/1235-maximum-profit-in-job-scheduling.java

@@ -0,0 +1,54 @@
+class Solution {
+    int[][] intervals;
+    Integer[] cache;
+
+    public int jobScheduling(int[] startTime, int[] endTime, int[] profit) {
+        int n = startTime.length;
+        intervals = new int[n][3];
+        cache = new Integer[n];
+
+        for (int i = 0; i < n; i++) {
+            intervals[i] = new int[]{startTime[i], endTime[i], profit[i]};
+        }
+
+        Arrays.sort(intervals, (a, b) -> Integer.compare(a[0], b[0]));
+
+        return dfs(0);
+    }
+
+    private int dfs(int i) {
+        if (i == intervals.length) {
+            return 0;
+        }
+
+        if (cache[i] != null) {
+            return cache[i];
+        }
+
+        // don't include
+        int res = dfs(i + 1);
+
+        // include
+        int j = binarySearch(intervals, i, intervals[i][1]);
+        cache[i] = res = Math.max(res, intervals[i][2] + dfs(j));
+
+        return res;
+    }
+
+    private int binarySearch(int[][] intervals, int start, int target) {
+        int left = start + 1;
+        int right = intervals.length - 1;
+
+        while (left <= right) {
+            int mid = left + (right - left) / 2;
+
+            if (intervals[mid][0] < target) {
+                left = mid + 1;
+            } else {
+                right = mid - 1;
+            }
+        }
+
+        return left;
+    }
+}