2001-2000-1999+1998+1997-1996+1995-1994-1993+1992+1991-1990+
2001-2000-1999+1998+1997-1996+1995-1994-1993+1992+1991-1990+
2001-2000-1999+1998+1997-1996+1995-1994-1993+1992+1991-1990+
2000+1999-1998-1997+1996+1995-1994-1993+1992+1991
1991+1992+1993+1994+1995+1996+1997+1998+1999+2000+2001+2001
1991+1992+1993+1994+1995+1996+1997+1998+1999+2000+2001+2002=
2003+1991-1992+1993-1994+1995-1996+1997-1998+1999-2000+2001-
1999+1998+1997-1996-1995-1994+1993+1992+1991-1990-1989-1988.
1999+1998+1997+1996-1995-1994-1993-1992+1991+1990+1989+1988-
计算:1999+1998+1997-1996-1995-1994+1993+1992+1991-1990-1989-19
数学问题1989+1991+1993+1995+1997+1999+2001/1990+1992+1994+1996+1
试说明1991^1992+1993^1994+1995^1996+1997^1998+1999^2000能被5整除
1998+1997+1996+1995+1994+1993+1992+1991=