HTMLify

func abs(n int) int {
    if n < 0 {
        return -n
    }
    return n
}
func makeGood(s string) string {
    var stack []rune
    for i:=0; i<len(s); i++ {
        if len(stack)>0 && abs(int(stack[len(stack)-1] - rune(s[i]))) == 32 {
            stack = stack[:len(stack)-1]
        } else {
            stack = append(stack, rune(s[i]))
        }
    }
    return string(stack)
}