diff --git a/.vscode/launch.json b/.vscode/launch.json
new file mode 100644
index 0000000..96ce58b
--- /dev/null
+++ b/.vscode/launch.json
@@ -0,0 +1,21 @@
+{
+    // Use IntelliSense to learn about possible attributes.
+    // Hover to view descriptions of existing attributes.
+    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": [
+        {
+            "type": "node",
+            "request": "launch",
+            "name": "Launch Program",
+            "runtimeExecutable": "C:\\Users\\AliensVN\\AppData\\Roaming\\fnm\\node-versions\\v20.17.0\\installation\\node.exe",
+            "skipFiles": [
+                "<node_internals>/**"
+            ],
+            "program": "${file}",
+            "outFiles": [
+                "${workspaceFolder}/**/*.js"
+            ]
+        }
+    ]
+}
\ No newline at end of file
diff --git a/src/common/custom_types/schedule.date.type.d.ts b/src/common/custom_types/schedule.date.type.d.ts
new file mode 100644
index 0000000..80d3c48
--- /dev/null
+++ b/src/common/custom_types/schedule.date.type.d.ts
@@ -0,0 +1,21 @@
+export type ScheduleDateJSON = {};
+
+export type ScheduleDate = Date | ScheduleDateJSON;
+
+/*
+
+[id:startTimeStamp - endTimeStamp, id:startTimeStamp - endTimeStamp, ...]
+
+*/
+
+
+1728206200 - 1728206300
+1728206400 - 1728206500
+1728206600 - 1728206700
+1728206800 - 1728206900
+1728207000 - 1728207100
+1728207200 - 1728207300
+1728207400 - 1728207500
+1728207600 - 1728207700
+
+
diff --git a/src/common/utils/datetime.utils.ts b/src/common/utils/datetime.utils.ts
new file mode 100644
index 0000000..d4290a3
--- /dev/null
+++ b/src/common/utils/datetime.utils.ts
@@ -0,0 +1,69 @@
+function getOverlapRange(
+  startA: number,
+  endA: number,
+  startB: number,
+  endB: number
+) {
+  const overlapStart = Math.max(startA, startB);
+  const overlapEnd = Math.min(endA, endB);
+
+  return overlapStart < overlapEnd ? { overlapStart, overlapEnd } : null;
+}
+
+function isOverlap(
+  startA: number,
+  endA: number,
+  startB: number,
+  endB: number
+) {
+  return getOverlapRange(startA, endA, startB, endB) !== null;
+}
+
+// Generate random time ranges for the schedulers
+function generateTimeRanges(count: number): { start: number; end: number }[] {
+  const ranges = [];
+  const startDate = new Date('2024-10-06T00:00:00Z').getTime();
+  for (let i = 0; i < count; i++) {
+    const start = startDate + Math.floor(Math.random() * 10000000); // Random start time
+    const end = start + Math.floor(Math.random() * 10000000); // Random end time after start
+    ranges.push({ start, end });
+  }
+  return ranges;
+}
+
+// Benchmark performance of overlap detection between two schedulers
+const schedulerA = generateTimeRanges(50);
+const schedulerB = generateTimeRanges(50);
+
+console.time('Overlap Benchmark');
+let overlapCount = 0;
+for (const rangeA of schedulerA) {
+  for (const rangeB of schedulerB) {
+    if (isOverlap(rangeA.start, rangeA.end, rangeB.start, rangeB.end)) {
+      overlapCount++;
+    }
+  }
+}
+console.timeEnd('Overlap Benchmark');
+
+console.log(`Total Overlaps Found: ${overlapCount}`);
+
+// Example usage with specific time ranges
+const startA = new Date('2024-10-06T10:00:00Z').getTime();
+const endA = new Date('2024-10-06T12:00:00Z').getTime();
+const startB = new Date('2024-10-06T11:00:00Z').getTime();
+const endB = new Date('2024-10-06T13:00:00Z').getTime();
+
+const overlapRange = getOverlapRange(startA, endA, startB, endB);
+if (overlapRange) {
+  console.log(
+    `Overlap Start: ${new Date(overlapRange.overlapStart).toISOString()}`
+  );
+  console.log(
+    `Overlap End: ${new Date(overlapRange.overlapEnd).toISOString()}`
+  );
+  
+  console.log('Is overlap: true');
+} else {
+  console.log('No overlap');
+}
\ No newline at end of file
diff --git a/src/restful/restful.controller.ts b/src/restful/restful.controller.ts
new file mode 100644
index 0000000..99c4305
--- /dev/null
+++ b/src/restful/restful.controller.ts
@@ -0,0 +1,46 @@
+import { Controller, Get, Post, Put, Delete, Param, Body } from '@nestjs/common';
+import { RestfulService } from './restful.service';
+import { ApiTags, ApiOperation, ApiResponse } from '@nestjs/swagger';
+
+@ApiTags('Restful')
+@Controller('restful')
+export class RestfulController {
+  constructor(private readonly restfulService: RestfulService) {}
+
+  @Get()
+  @ApiOperation({ summary: 'Get all items' })
+  @ApiResponse({ status: 200, description: 'Returns all items.' })
+  getAllItems() {
+    return this.restfulService.getAllItems();
+  }
+
+  @Get(':id')
+  @ApiOperation({ summary: 'Get an item by ID' })
+  @ApiResponse({ status: 200, description: 'Returns the item with the given ID.' })
+  getItem(@Param('id') id: string) {
+    return this.restfulService.getItem(id);
+  }
+
+  @Post()
+  @ApiOperation({ summary: 'Create a new item' })
+  @ApiResponse({ status: 201, description: 'The item has been successfully created.' })
+  createItem(@Body() createDto: any) {
+    return this.restfulService.createItem(createDto);
+  }
+
+  @Put(':id')
+  @ApiOperation({ summary: 'Update an item' })
+  @ApiResponse({ status: 200, description: 'The item has been successfully updated.' })
+  updateItem(@Param('id') id: string, @Body() updateDto: any) {
+    return this.restfulService.updateItem(id, updateDto);
+  }
+
+  @Delete(':id')
+  @ApiOperation({ summary: 'Delete an item' })
+  @ApiResponse({ status: 200, description: 'The item has been successfully deleted.' })
+  deleteItem(@Param('id') id: string) {
+    return this.restfulService.deleteItem(id);
+  }
+}
+
+export default RestfulController;
diff --git a/src/users/dto/create-user.dto.ts b/src/users/dto/create-user.dto.ts
new file mode 100644
index 0000000..e69de29
diff --git a/src/users/dto/update-user.dto.ts b/src/users/dto/update-user.dto.ts
new file mode 100644
index 0000000..e69de29