我正在寻找一个e-LMC扩展的小型计算机程序,它将接受不确定的输入并对其进行气泡排序。我需要有更多的连续输入,然后做气泡排序。
INP //read 1st value
STA 0 // for store
INP // read 2nd value
STA 1 // store
INP // read 3rd value
STA 2 // store
LDA 1 // LOOP 1, STEP 1:
SUB 0 //
BRP STEP2 // if R0 and R1 are in order, don't swap them
LDA 1 // Begin swapping registers
STA 3
LDA 0
STA 1 // R1 = R0
LDA 3
STA 0 //R0 = temp
STEP2 LDA 2 // LOOP 1, STEP 2
SUB 1
BRP STEP3 // If R1 and R2 are in order, don't swap them
LDA 2 // Begin swapping registers
STA 3 // temp =R2
LDA 1
STA 2 //R2=R1
LDA 3
STA 1 // R1 = temp
STEP3 LDA 1 // LOOP 2, STEP 1
SUB 0
BRP STEP4 // if R0 andR1 are in order, don't swap them
LDA 1 // Begin swapping registers
STA 3 // temp = R1
LDA 0
STA 1 //R1=R0
LDA 3
STO 0 // R0 = temp
STEP4 LDA 0
OUT
LDA 1
OUT
LDA 2
OUT
HLT
由于我不熟悉e-LMC,我在这里提供了一个纯LMC实现。当然,缺点是LMC的空间有限。由于以下代码占用了62个邮箱(不包括输入数组(,因此最多可以输入38个值(这一点未经验证(。
我选择用一个终止的0值来标记输入的末尾,即要排序的值不能包括0。
正如您在评论中所指出的,此解决方案在很大程度上依赖于自修改代码。用get***
、set***
和cmp***
标记的所有指令都会动态更改为指向数组中的右侧元素。
你可以在这个片段中运行这个代码(它加载了一个模拟器(:
#input: 5 2 4 1 3 0
LDA setfirst
STA setcurr1
input INP
setcurr1 STA array
BRZ isempty
LDA setcurr1
ADD one
STA setcurr1
BRA input
isempty LDA array
BRZ zero ; empty array
sort LDA getfirst ; init "curr" indices
STA getcurr1
STA getcurr2
LDA setfirst
STA setcurr2
LDA cmpfirst
STA cmpcurr
STA issorted ; bool: assume sorted
loop LDA getcurr1 ; set "next" indices
ADD one
STA getnext1
STA getnext2
LDA setcurr2
ADD one
STA setnext
getnext1 LDA array
BRZ check ; end of array
cmpcurr SUB array
BRP inc ; no swap needed
getcurr1 LDA array ; swap
STA temp
getnext2 LDA array
setcurr2 STA array
LDA temp
setnext STA array
LDA zero
STA issorted ; was not sorted yet
inc LDA getnext1 ; increment "cur" indices
STA getcurr1
LDA setnext
STA setcurr2
LDA cmpcurr
ADD one
STA cmpcurr
BRA loop
check LDA issorted
BRZ sort
getcurr2 LDA array
BRZ zero ; all done
OUT
LDA getcurr2
ADD one
STA getcurr2
BRA getcurr2
; constants:
zero HLT
one DAT 1
getfirst LDA array
setfirst STA array
cmpfirst SUB array
; variables:
issorted DAT ; boolean
temp DAT ; for swapping
array DAT ; start of array
<script src="https://cdn.jsdelivr.net/gh/trincot/lmc@v0.77/lmc.js"></script>
正如你所写的,e-LMC是LMC的扩展,有更多的寄存器和寻址方法,我想把它变成一个可以利用这些扩展的程序并不难。