Schwarz et al.訂出基因複製向量間的距離，以探討正常基因組與腫瘤基因組的差距，並提出計算距離的演算法MEDICC，但並未分析計算複雜度，且在某些情況下，會是指數型態。之後Zera et al.提出線性時間的演算法，但我們發現在推導過程中，有些地方並不正確，確認Zeira et al.演算法的結論有誤。另外我們提出新的演算法，對原方法做了若干修正。

Schwarz et al. set the distance between copy number profiles to explore the gap between normal genome and tumor genome. They proposed the MEDICC algorithm for calculating distance, but did not analyze its complexity. However, in some cases, MEDICC would be exponential time. After that, Zeira et al. proposed a linear time algorithm, but we found the process that leading out the result has something wrong. So we propose a new algorithm and make some changes to the original method.