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 dZEkybr+NMJ6obo5OOySq/cxqv3I5p/tnVeKG3PK3oj2/lvpTefmlqGlxL+yCObM