adding nginx page & simulation endpoint

ASP.NET/Controllers/SimulationController.cs

@@ -0,0 +1,26 @@
+using Microsoft.AspNetCore.Mvc;
+using TCC.Services;
+
+namespace TCC.Controllers
+{
+    [ApiController]
+    [Route("simulation")]
+    public class SimulationController : ControllerBase
+    {
+        public SimulationController()
+        {
+        }
+
+        [HttpGet("harmonic-progression")]
+        public async Task<IActionResult> GetHarmonicProgression([FromQuery] int n)
+        {
+            float sum = 0;
+            for (int i = 1; i <= n; i++)
+            {
+                sum += 1.0f / i;
+            }
+
+            return Ok(sum);
+        }
+    }
+}