Digital Electronics

A contour integral is defined as $I_n = \oint_C \frac{dz}{(z-1)^n + z^{n/2}}$ where $n$ is a positive integer and $C$ is the closed contour consisting of the real line segment from $-100$ to $+100$ and the upper semicircle traversed in the counter-clockwise sense in the complex plane $z = x + iy$. The value of $\sum_{n=1}^\infty I_n$ (in integer) is _