The government has decided to operate intercity trains from May 31 to June 15 through selling 50 percent tickets.   Railways Minister Md Nurul Islam Sujan came up with information on Thursday.   He said the decision to sell 50 percent tickets has been taken so that passengers can travel maintaining distance from each other.     A meeting will be held in this regard on May 30, said the minister.   The government has decided to allow limited operation of public transport, State Minister for Public Administration Farhad Hossain told UNB on Wednesday night.   Public transports – buses, trains and vessels – will have to maintain health guidelines, Hossain said.