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.
2006
2005
1995
2000
2004
2003
2002
2007
2009
2008
1952
1983
1946
2001
1991
2022
2021
