Snapping seven days of losses, the Sensex at the Bombay Stock Exchange gained 23 points, or 0.2 percent, to close at 18,705, today, on buying by funds amid firm European markets. The Nifty at the National Stock Exchange edged up 8 points, or 0.1 percent, to 5,642.Stock markets in Japan, China, Hong Kong, Singapore and South Korea ended mixed.