答案是-50.
依次把首尾的相加为-100+(1+99)+(-2-98).......(-50-50)+50=-50
1(-2)(3)(-4)(5)...(99)(-100)
=199!
=2.72539213975073E+78
使用程序做个简单的计算:
Private Sub Command1_Click()
Dim Num As Double
Num = 1
For i = 1 To 100
Num = Num * (-1) ^ (i + 1) * i
i = i + 1
Next i
Text1.Text = Num
End Sub
答案:2.72539213975073E+78
里面有50个负数,即25对负数,所以乘积一定是正数.
那1*(-2)*3*(-4)*...*(-100)
=1*2*3*...*100
=100!
参考资料：||
