Add Palindromic Number in Wren (#4392)

Author: Kaamkiya

archive/w/wren/palindromic-number.wren

@@ -0,0 +1,28 @@
+import "os" for Process
+
+var args = Process.arguments
+
+if (args.count < 1 || args[0].count < 1) {
+  System.print("Usage: please input a non-negative integer")
+  Fiber.suspend()
+}
+
+var s = args[0]
+var n = Num.fromString(s)
+
+if (n == null || n < 0) {
+  System.print("Usage: please input a non-negative integer")
+  Fiber.suspend()
+}
+
+var a = ""
+
+for (c in s) {
+  a = c + a
+  if (c == ".") {
+    System.print("Usage: please input a non-negative integer")
+    Fiber.suspend()
+  }
+}
+
+System.print(a == s)