Initial data commit

Task/100-doors/JavaScript/100-doors-11.js

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+"use strict";
+
+// Doors can be open or closed.
+const open = "O";
+const closed = "C";
+
+// There are 100 doors in a row that are all initially closed.
+const doorsCount = 100;
+const doors = [];
+for (let i = 0; i < doorsCount; doors[i] = closed, i++);
+
+// You make 100 passes by the doors, visiting every door and toggle the door (if
+// the door is closed, open it; if it is open, close it), according to the rules
+// of the task.
+for (let pass = 1; pass <= doorsCount; pass++)
+    for (let i = pass - 1; i < doorsCount; i += pass)
+        doors[i] = doors[i] == open ? closed : open;
+
+// Answer the question: what state are the doors in after the last pass?
+doors.forEach((v, i) =>
+    console.log(`Doors ${i + 1} are ${v == open ? 'opened' : 'closed'}.`));
+
+// Which are open, which are closed?
+let openKeyList = [];
+let closedKeyList = [];
+for (let door of doors.entries())
+    if (door[1] == open)
+        openKeyList.push(door[0] + 1);
+    else
+        closedKeyList.push(door[0] + 1);
+console.log("These are open doors: " + openKeyList.join(", ") + ".");
+console.log("These are closed doors: " + closedKeyList.join(", ") + ".");
+
+// Assert:
+const expected = [];
+for (let i = 1; i * i <= doorsCount; expected.push(i * i), i++);
+if (openKeyList.every((v, i) => v === expected[i]))
+    console.log("The task is solved.")
+else
+    throw "These aren't the doors you're looking for.";