There are three iron wires, one is 16m long, the other is 20m long, and the other is 30m long. They should be cut into small pieces of the same length. As a result, there was 1m left on the first one, 2m on the second one, and nothing left on the third one. How many meters is the longest section?
有三根铁丝，一根长16m，一根长20m，一根长30m，要把它们截成同样长的小段．结果第一根余下1m，第二根余下2m，第三根刚好没有剩余．每小段最长有多少米？
<result>3</result>