day 28

Author: sachuverma

Leetcode Daily Challenge/August-2021/28. Maximum Profit in Job Scheduling.cpp

@@ -0,0 +1,73 @@
+/*
+Maximum Profit in Job Scheduling
+================================
+
+We have n jobs, where every job is scheduled to be done from startTime[i] to endTime[i], obtaining a profit of profit[i].
+
+You're given the startTime, endTime and profit arrays, return the maximum profit you can take such that there are no two jobs in the subset with overlapping time range.
+
+If you choose a job that ends at time X you will be able to start another job that starts at time X.
+
+Example 1:
+Input: startTime = [1,2,3,3], endTime = [3,4,5,6], profit = [50,10,40,70]
+Output: 120
+Explanation: The subset chosen is the first and fourth job. 
+Time range [1-3]+[3-6] , we get profit of 120 = 50 + 70.
+
+Example 2:
+Input: startTime = [1,2,3,4,6], endTime = [3,5,10,6,9], profit = [20,20,100,70,60]
+Output: 150
+Explanation: The subset chosen is the first, fourth and fifth job. 
+Profit obtained 150 = 20 + 70 + 60.
+
+Example 3:
+Input: startTime = [1,1,1], endTime = [2,3,4], profit = [5,6,4]
+Output: 6
+
+Constraints:
+1 <= startTime.length == endTime.length == profit.length <= 5 * 104
+1 <= startTime[i] < endTime[i] <= 109
+1 <= profit[i] <= 104
+*/
+
+class Solution {
+public:
+    int memo[50001];
+    
+    int find(vector<vector<int>>& arr, int target, int l, int r){
+      while(l < r){
+        int m = l+(r-l)/2;
+        if(arr[m][0] >= target) 
+          r = m;
+        else l = m+1;
+      }
+      if(arr[r][0] >= target) return r;
+      return -1;
+    }
+    
+    int dfs(vector<vector<int>>& jobs, int index) {
+        if(index >= jobs.size()) return 0;
+        
+        if(memo[index] != -1) return memo[index];
+        
+        int ans = 0;
+        ans = max(ans, dfs(jobs, index+1));
+        
+        int next = find(jobs, jobs[index][1], index+1, jobs.size()-1);
+        
+        ans = max(ans, jobs[index][2] + dfs(jobs, next));
+        return memo[index] = ans;
+    }
+    
+    int jobScheduling(vector<int>& startTime, vector<int>& endTime, vector<int>& profit) {
+        vector<vector<int>> jobs;
+        for(int i = 0; i < startTime.size(); ++i) {
+            jobs.push_back({startTime[i], endTime[i], profit[i]});
+        }
+        
+        memset(memo, -1, sizeof memo);
+        
+        sort(jobs.begin(), jobs.end());
+        return dfs(jobs, 0);
+    }
+};

Leetcode Daily Challenge/August-2021/README.md

@@ -29,4 +29,6 @@
 | 25. | [Sum of Square Numbers](https://leetcode.com/explore/challenge/card/august-leetcoding-challenge-2021/616/week-4-august-22nd-august-28th/3918/)                            |                  [cpp](./25.%20Sum%20of%20Square%20Numbers.cpp)                   |
 | 26. | [Verify Preorder Serialization of a Binary Tree](https://leetcode.com/explore/challenge/card/august-leetcoding-challenge-2021/616/week-4-august-22nd-august-28th/3920/) | [cpp](./26.%20Verify%20Preorder%20Serialization%20of%20a%20Binary%20Tree.cpp) |
 | 27. | [Longest Uncommon Subsequence II](https://leetcode.com/explore/challenge/card/august-leetcoding-challenge-2021/616/week-4-august-22nd-august-28th/3921/) | [cpp](./27.%20Longest%20Uncommon%20Subsequence%20II.cpp) |
+| 28. | [Maximum Profit in Job Scheduling](https://leetcode.com/explore/challenge/card/august-leetcoding-challenge-2021/616/week-4-august-22nd-august-28th/3950/) | [cpp](./28.%20Maximum%20Profit%20in%20Job%20Scheduling.cpp) |
+| 28. | []() | [cpp](./28.%20.cpp) |
 | 28. | []() | [cpp](./28.%20.cpp) |