func PadLeft(s, c string, n int) string {
	L := len(s)
	if L > n {
		return s
	}
	return strings.Repeat(c, (n-L)) + s
}
func PadLeft(s, c string, n int) string {
	L := len(s)
	if L > n {
		return s
	}
	return strings.Repeat(c, (n-L)) + s
}
// PadLeft pads s on left side with c until it has length of n.