There is a small rod of 1-10 cm in the box. After taking out the small rods of 3 cm and 7 cm, at least how many cm of small rods can be taken to form a triangle.
盒中有1～10cm的小棒各一根，取出3cm和7cm的小棒后，至少再取多少cm的小棒才能围成一个三角形．
<result>5</result>