Add toPounds function for currency conversion

Implemented the toPounds function to convert pence to pounds.

Author: cywong-dev

Sprint-2/3-mandatory-implement/3-to-pounds.js

@@ -4,3 +4,23 @@
 // You will need to declare a function called toPounds with an appropriately named parameter.
 
 // You should call this function a number of times to check it works for different inputs
+function toPounds(penceString)
+{
+  const penceStringWithoutTrailingP = penceString.substring(
+    0,
+    penceString.length - 1
+  );
+
+  const paddedPenceNumberString = penceStringWithoutTrailingP.padStart(3, "0");
+  const pounds = paddedPenceNumberString.substring(
+    0,
+    paddedPenceNumberString.length - 2
+  );
+
+ const pence = paddedPenceNumberString
+  .substring(paddedPenceNumberString.length - 2)
+  .padEnd(2, "0");
+
+ return(`£${pounds}.${pence}`);
+
+}