Definition: In this task, you're given a short article. Your job is to classify the article based on its category. Use the following classification labels, 0. World, 1. Sports, 2. Business, 3. Science or Technical. Label the text "0" if it contains information related to world. Label the text "1" if it contains information related to sports. Label the text "2" if it contains information related business. Label the text "3" if it contains science or technical related information. 
Input: Martin Retires After Losing at U.S. Open (AP) AP - There would be no fifth set this time for Todd Martin. Martin announced his retirement Monday after he failed to close out the fourth set in a 4-6, 6-4, 6-4, 7-5 loss to No. 31 Fabrice Santoro in the first round of the U.S. Open.
