LESSON 166 OF 415 · PROJECTS: EVERYDAY PROGRAMS

Shopping Cart V4 - Cart Sum in Swift

Practice

Use a for loop over parallel arrays to compute a running total across several items.

You start with:

        let items = ["Shirt", "Pants", "Shoes", "Hat"]
        let prices = [25, 40, 60, 15]
        let quantities = [2, 1, 1, 3]

Build:

Shirt x2: $50
Pants x1: $40
Shoes x1: $60
Hat x3: $45
Total: $195

Rules:

For each index i, the item's subtotal is prices[i] * quantities[i].
Build one line per item, in order, in the format "Name xQ: $subtotal" (e.g. "Shirt x2: $50").
Add every subtotal to a running total.
Finish with a "Total: $..." line.
Join all the lines with a newline "\n" into one string result, then print it with print(result).

Use var lines = [String]() and var total = 0 before the loop, then append each formatted line.

Call lines.joined(separator: "\n") at the end.

        let items = ["Shirt", "Pants", "Shoes", "Hat"]
        let prices = [25, 40, 60, 15]
        let quantities = [2, 1, 1, 3]

        var lines = [String]()
        var total = 0
        for i in items.indices {
            let subtotal = prices[i] * quantities[i]
            total += subtotal
            lines.append("\(items[i]) x\(quantities[i]): $\(subtotal)")
        }
        lines.append("Total: $\(total)")
        let result = lines.joined(separator: "\n")
        print(result)

STEP 1 OF 9

Guided

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Shopping Cart V4 - Cart Sum in Swift

Shopping Cart V4 in Swift