function shopping_list(data) {
    let products = data.shift().split("!")

    for (let i of data) {
        let command_data = i.split(' ')
        let command = command_data[0]

        if (command === 'Urgent') {
            let current_item = command_data[1]
            if (!products.includes(current_item)) {
                products.unshift(current_item)
            }
        } else if (command === 'Unnecessary') {
            let elementToRemove = command_data[1]
            if (products.includes(elementToRemove)) {
                products = products.filter(item => item !== elementToRemove)
            }
        } else if (command === 'Correct') {
            let old_item = command_data[1]
            let new_item = command_data[2]
            if (products.includes(old_item)) {
                let index = products.indexOf(old_item)
                products[index] = new_item

            }
        } else if (command === 'Rearrange ') {
            let rearrange_item = command_data[1]
            if(products.includes(rearrange_item)) {
                let rearrange_index = products.indexOf(rearrange_item)
                products.splice(rearrange_index, 1)
                products.push(rearrange_item)
            }
        }
    }
    console.log(products.join(', '))
}

// shopping_list(
//     ["Milk!Pepper!Salt!Water!Banana",
//         "Urgent Salt",
//         "Unnecessary Grapes",
//         "Correct Pepper Onion",
//         "Rearrange Grapes",
//         "Correct Tomatoes Potatoes",
//         "Go Shopping!"])

shopping_list(["Tomatoes!Potatoes!Bread",
    "Unnecessary Milk",
    "Urgent Tomatoes",
    "Go Shopping!"])