這是關於堆疊指標的問題
Given the following 8 possible solution for a POP or a PUSH operation in a
STACK : 1.Read from Mem(SP), Decrement SP ;
2.Read from Mem(SP), Increment SP ;
3.Decrement SP, Read from Mem(SP) ;
4.Increment SP, Read from Mem(SP) ;
5.Write to Mem(SP), Decrement SP ;
6.Write to Mem(SP), Increment SP ;
7.Decrement SP, Write to Mem(SP) ;
8.Increment SP, Write to Mem(SP) ;
(1) Solution of a PUSH operation for a Last Full stack that grows ascending.
8.Increment SP, Write to Mem(SP) ;
(2) Solution of a POP operation for a Next Empty stack that grows descending.
4.Increment SP, Read from Mem(SP) ;
(3) Solution of a PUSH operation for a Next Empty stack that grows ascending.
6.Write to Mem(SP), Increment SP ;
(4) Solution of a POP operation for a Last Full stack that grows descending.
2.Read from Mem(SP), Increment SP ;
請問這4題題目該如何翻譯呢?答案又為何是這4個呢?
stack的存取規則不是PUSH時 SP<-SP-1 Stack(sp)<-data
POP 時 data<-Stack(sp) SP<-SP+1 嗎?
題目後面的 ascending descending 為何有兩種sp移動的方向呢?
希望高手幫忙解答^^~
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