Update README.md

README.md

@@ -292,8 +292,9 @@ MILP instances in this library are stored as text strings. You can download the
 from datasets import load_dataset
 
 dataset = load_dataset("weiminhu/D-MIPLIB","CA-easy", split='test')
-test_instance = dataset[0]['MILP']
-ins_save_path = "./test_instance.lp"
+test_id = 0
+test_instance = dataset[test_id]['MILP']
+ins_save_path = "./test_instance_%s.lp" % test_id
 with open(ins_save_path, "w") as file:
     tmp=test_instance[2:-1]
     tmp=tmp.replace("\\n","\n")