local function string_split(str, exp)
	local result = {}
	local strlen = #str
	local index = 1
	while index < strlen do
		local start_pos, end_pos = string.find(str, exp, index)
		if start_pos == nil then
			break;
		else
			local match_str = string.sub(str, index, start_pos - 1)
			result[#result + 1] = match_str
			index = end_pos + 1
		end
	end
	result[#result + 1] = string.sub(str, index)
	
	return result
end 

local function format_time(secs, format)
	local format = string_split(format, ":")
	local radix = {24, 60, 60}
	local time_str = "";
	local base_value, base_name, value
	local i = #radix
	while i > 0 do
		base_value = radix[i]
		base_name = format[i + 1]
		
		value = secs % base_value
		
		if value > 0 then
			if base_name then
				time_str = value .. base_name .. time_str
			end
		end
		
		secs = math.floor(secs / base_value)
		
		i = i - 1
	end
	
	if secs > 0 then
		time_str = secs .. format[i + 1] .. time_str
	end
	
	return time_str 
end

local function main()	

	print(format_time(math.floor(200000 / 60) * 60, "天:小时:分钟:秒"))
	
end
main()