package main

import (
    "fmt"
)

func plusOne(A []int) []int {
    carry := 1
    for i := len(A) - 1; i >= 0; i-- {
        A[i] = A[i] + carry
        carry = A[i] / 10
        A[i] = A[i] % 10
    }

    var Ap1 []int
    if carry > 0 {
        Ap1 = append([]int{carry}, A...)
    } else {
        Ap1 = A
    }

    firstNonZero := 0
    for firstNonZero = range Ap1 {
        if Ap1[firstNonZero] != 0 {
            break
        }
    }
    return Ap1[firstNonZero:]
}

func main() {
    fmt.Println(plusOne([]int{0, 0, 9}))
}