题目给的是20bit "word address"，cahce有16个word size(a)1.需要16个block,index=4,word offest=0,tag=20-4(a)2.4个block,index=2,word offest=2,tag=20-2-2(a)2.共8个block,每个set两个block,set number=4,index=2word offset=1,tag=20-2-1cache中offset分成byte offset跟word offsetbyte offset 一般都是为2,1word=4bytesword offset 看一个block有的word数量(b)(valid bit + tag bit + block有的word转为bit)*blocksword address/word offset^2 = block addressblock address/index^2 = tag numberblock address mod index^2 = index number