Implement toPounds function to convert pence to formatted pounds and add test cases

Author: TTiamiyu

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

@@ -4,3 +4,36 @@
 // 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) {
+  // 1. Remove the trailing 'p'
+  const penceStringWithoutTrailingP = penceString.substring(
+    0,
+    penceString.length - 1
+  );
+
+  // 2. Pad with zeros to ensure we always have at least 3 digits (e.g., "5" becomes "005")
+  const paddedPenceNumberString = penceStringWithoutTrailingP.padStart(3, "0");
+
+  // 3. Extract the pounds (everything except the last two digits)
+  const pounds = paddedPenceNumberString.substring(
+    0,
+    paddedPenceNumberString.length - 2
+  );
+
+  // 4. Extract the pence (just the last two digits)
+  const pence = paddedPenceNumberString
+    .substring(paddedPenceNumberString.length - 2)
+    .padEnd(2, "0");
+
+  // 5. Return the formatted currency string
+  return `£${pounds}.${pence}`;
+}
+
+// --- Test Cases ---
+// Calling the function multiple times to check it works for different inputs
+console.log(toPounds("399p")); // Expected output: "£3.99"
+console.log(toPounds("5p")); // Expected output: "£0.05"
+console.log(toPounds("2500p")); // Expected output: "£25.00"
+console.log(toPounds("99p")); // Expected output: "£0.99"
+console.log(toPounds("10000p")); // Expected output: "£100.00"