Create 1882-process-tasks-using-servers.js

Author: aadil42

javascript/1882-process-tasks-using-servers.js

@@ -0,0 +1,57 @@
+/**
+ * MinPriorityQueue | Simulation
+ * Time O(n*log(n)) | Space O(n)
+ * https://leetcode.com/problems/process-tasks-using-servers/
+ * @param {number[]} servers
+ * @param {number[]} tasks
+ * @return {number[]}
+ */
+var assignTasks = function(servers, tasks) {
+    
+    const toBeCompleted = new MinPriorityQueue({
+        compare: (a,b) => {
+            if(a[0] === b[0]) return a[1] - b[1];
+            return a[0] - b[0];
+        }
+    });
+
+    const freeServers = new MinPriorityQueue({
+        compare: (a,b) => {
+            if(a[0] === b[0]) return a[1] - b[1];
+            return a[0] - b[0];
+        }
+    });
+
+    for(let i = 0; i < servers.length; i++) {
+        const weight = servers[i];
+        const idx = i;
+        freeServers.enqueue([weight, idx]);
+    }
+
+    let sec = 0;
+    const result = [];
+
+    for(let i = 0; i < tasks.length; i++) {
+        sec = Math.max(i, sec);
+
+        // if the we don't have server available then jump to the next imidiate 
+        // time when the server will be available.
+        if(freeServers.isEmpty()) {
+            sec = toBeCompleted.front()[0];
+        }
+         while(!toBeCompleted.isEmpty() && 
+              toBeCompleted.front()[0] <= sec
+        ) {
+            const [endTime, serverIdx] = toBeCompleted.dequeue();
+            const weight = servers[serverIdx];
+            freeServers.enqueue([weight, serverIdx]);
+        }
+
+        const [weight, serverIdx] = freeServers.dequeue();
+        const timeToBeTaken = tasks[i];
+        result.push(serverIdx);
+        toBeCompleted.enqueue([sec+timeToBeTaken, serverIdx]);
+    }
+
+    return result;
+};