What row operation does multiplication by the following matrix perform?

[1000001000001000001000011]\displaystyle {\left[\begin{array}{ccccc} {1}&{0}&{0}&{0}&{0}\\{0}&{1}&{0}&{0}&{0}\\{0}&{0}&{1}&{0}&{0}\\{0}&{0}&{0}&{1}&{0}\\{0}&{0}&{0}&-{1}&{1}\end{array}\right]}