  In this paper, we will introduce the quantum circuit simulator we developed
in C++ environment. We devise a novel method for efficient memory handling
using linked list structures that enables us to simulate a quantum circuit of
up to 20 qubits in a reasonable time. Our package can simulate the activity of
any quantum circuit constructed by the user; it will also be used to understand
the robustness of certain quantum algorithms such as Simons and Shors.
