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 gALdK51vdS1cU18YY+LdG7FBEcLdzwBmj/s7oQHVrTCTJZWyqrAUTPjA/DqupGFF