There are 12 steps in a staircase. If it is stipulated that only one or two steps can be climbed at a time, how many different ways are there to climb up to the 12th step?
有一楼梯共12级，如规定每次只能跨上一级或两级，要登上第12级，共有多少不同的走法．
<result>233</result>