我創建了這個程序package mainimport "fmt"var bankAccount = 12342func withdraw(withdrawAmnt int) int { //withdraw function, return int    bankAccount -= withdrawAmnt    if bankAccount < 0 {        bankAccount += withdrawAmnt //bankaccount cannot go negative        return 1    } else { return 0 }}func deposit(depositAmnt int) {    bankAccount += depositAmnt}func main() {    var choice int    var withdraw int    var deposit int    fmt.Printf("%d \n 1. withdraw \n 2. deposit \n 3. exit")    fmt.Scanln(&choice)    switch choice {        case 1:            fmt.Scanln(&withdraw)            if withdraw(withdraw) != 0 {                fmt.Println("Not succesful: not enough money (you're broke)")            }        case 2:            fmt.Scanln(&deposit)            deposit(deposit)        case 3:            os.Exit()    }}我不斷得到這個錯誤：不能調用非函數存款（類型int），也不能調用非功能存款（類型int）。