1+3+5+……+99-(2+4+6+……+98+100)
问题描述:
1+3+5+……+99-(2+4+6+……+98+100)
答
[(1+99)*50]/2-[(100+2)*50]/2=-50
答
1+3+5+……+99-(2+4+6+……+98+100)
=(1-2)+(3-4)+……+(99-100)
= -1×50
= -50