chore: Add sample problem from competition archive

Author: icyJoseph

swift/sample_problem.swift

@@ -0,0 +1,23 @@
+import Foundation
+
+let T = Int(readLine()!)!
+
+for ti in 1 ... T {
+    let line = readLine()!.components(separatedBy: " ")
+
+    let N = Int(line[0])!
+
+    let M = Int(line[1])!
+
+    let C = readLine()!.components(separatedBy: " ").map { Int($0)! }
+
+    var sum = 0
+
+    for Ci in C {
+        sum += Ci
+    }
+
+    let modulo = sum % M
+
+    print("Case #\(ti): \(modulo)")
+}

tests/sample_problem.in

@@ -0,0 +1,5 @@
+2
+7 3
+1 2 3 4 5 6 7
+5 10
+7 7 7 7 7