excel表，怎样计算分钟差，也就是时间差

A列为数据的话 B1输入 =TEXT(SUM(IF(A1:A10="",0,RIGHT(A1:A10,LEN(A1:A10)-FIND("-",A1:A10))*1-LEFT(A1:A10,FIND("-",A1:A10)-1)*1)),"hh:mm") 或者 =TEXT(SUM(IF(A1:A10="",0,RIGHT(A1:A10,5)-LEFT(A1:A10,5))),"