图1-7是用14根火柴拼成的平房,要想把它变成楼房,请问至少需要移动几根火柴?
图1-7 YuS6cHqBObgup0xmB30PANPHYhvGE/q0A5FnHZNVZ0MgM+7tKPoKz/F3w4jwoo6O