import Foundation

let input = try String(contentsOfFile: CommandLine.arguments[1])
let commandPattern = try Regex(#"mul\(([0-9]+),([0-9]+)\)|don't\(\)|do\(\)"#)

var enabled: Bool = true
var sum: Int = 0
for cmd in input.matches(of: commandPattern) {
    switch cmd.output[0].substring {
    case "don't()":
        enabled = false
    case "do()":
        enabled = true
    default:
        if enabled {
            sum += Int(cmd.output[1].substring!)! * Int(cmd.output[2].substring!)!
        }
    }
}
print(sum)