The doors of the jam produced by a company do not open. In order for them to be able to sell their jam, they reward the one who can open the jam. All the people try to open the door of the jam.
2009
2025
1981
1982
1993
2013
2018
2011
2010
2021
2007
2002
2001
1948
2016
1984
2003
2017
