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代入以下代码,得:11,9,4,2,1,6 滑稽~6 c) Z: e/ u1 L7 m- [7 S
4 A, E, d5 E7 ~6 {5 U5 `#include <iostream>
, g3 R% J5 o1 J) Z' ^#include <string.h>* L( b( C3 c0 e, w+ }! w
using namespace std;
% t. C, C" f8 f7 Qtemplate <class T>
* {/ Y( ^- Q+ Z6 E+ s0 F$ Pclass Node
( d/ [7 Z: n( H% K{
2 f- T* A2 s0 b1 f) R6 _# L" Rpublic:5 D# N, D( ^+ U% Y7 r* \0 B, T
T data;7 t# E9 |! p9 e: n
Node<T> *next;, X" H& K) u0 Z% h
Node()
9 w8 n" Y3 `) w6 ~5 ] {
' P4 ?( H4 R( A) A this->next = NULL;
) B! I. y( k! x$ a- T( d* U }4 w' E3 q1 X0 P1 U- Q f; G% W
Node(T data,Node<T> *next=NULL)+ L, e! d( n, }; N3 f% I# E
{
7 x1 }3 J V9 w1 U% s3 { this->data = data;
8 e6 e% I4 T: r5 V; } this->next = next;
( [9 `8 {0 @4 Y: Z% D- x5 J8 V }
9 y/ V7 {& m ^$ q$ D( p};1 L1 G( `) @+ `0 g+ c6 B) O( K
8 L6 n/ T7 {) c" t; c8 |" Rtemplate <class T>
: C8 v0 I& r# ^, h+ I$ F3 }class LinkedStack5 ]9 ^' _3 W# U: T/ x% P
{
; Y' o! a+ g7 N% F& w. C! aprivate:
, e# L1 S$ O0 R3 u Node<T> *top;- w% c0 } w8 m) ^! N
public:
8 j' m2 ^: {7 d% b, W7 ^: S LinkedStack();. K0 j2 N; H/ \" O! I, g' T
~LinkedStack();
6 _0 ^$ n; X( z* ^9 @/ X; z5 C bool isEmpty();
, K5 } |" h! _! O) i void push(T x);+ N+ Q- J7 G+ ^( V: b
T pop();9 X6 |( J/ |5 O. E9 o1 J
T get();
" R0 h8 f' u* C7 q5 D};
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template <class T>
* [9 Y. D* p7 U% s+ QLinkedStack<T>::LinkedStack(), w* k" E; X5 p* d3 h& i
{
4 j+ v0 E0 c [ s, |" k, r, K top = NULL;
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5 D) a0 _1 i% x( K `2 p3 ktemplate <class T>: {% ^7 p* Q) Y6 Z0 {
LinkedStack<T>::~LinkedStack()( C% P+ q5 O6 k" O- Q
{7 t& U* U* k& t! i/ V2 d
Node<T> *p = top;1 B9 r. V2 ~$ Q4 D7 _2 W
Node<T> *q;# w6 y* q" m! x7 j/ r# ?7 _
while(p!=top)# _( n1 x5 u+ J. ~8 l
{$ ~3 D- a4 U# I% S7 d( _
q = p;
( w/ [% V* C1 y* ~- x p = p->next;; X0 x& Y( j7 A7 Q6 S4 d1 G$ P
delete p;
: }1 `4 X/ i5 Z# c! [( V }
" k$ k0 K5 P4 H5 B top = NULL;
4 d0 {7 ^* I6 z3 a+ `! v) x2 [}
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template <class T> s/ X- x# G; |9 r0 a! K
bool LinkedStack<T>::isEmpty(); K' n$ o5 h# K, F+ l
{! C; J: N) g9 @
return top == NULL;
/ O4 r0 }5 o# P* {% l9 f}
1 n* p+ o5 M2 D7 T0 y
H+ X' {4 P6 v* H- H8 V. ?% M* Stemplate <class T>
* ]% @* ^* u6 e+ r. Y' |+ b5 i, ^void LinkedStack<T>::push(T x)0 v- a2 r; B2 m$ T' N
{
) K8 k6 X# x$ Y/ m' s top = new Node<T>(x,top);( J6 }$ T4 G8 T5 ]0 |% b
}6 N9 @* T! P9 x; l# E4 `
" E# C; v" H* x. y8 o+ H
template <class T>
$ N8 Z B$ g& } B5 H+ D: gT LinkedStack<T>::pop()
! o5 E% D" A) B) d{
# k0 c1 u1 { p( T1 h0 o. R if(!isEmpty())9 H5 J& y& ^) d ~) Q( E+ I( s
{
- o( y E9 C$ I& q! } T x = top->data;
5 X% z% k9 ]" \1 v- s5 n Node<T> *p = top;: Z% Q8 h* l( s5 S
top = top->next;
' ^! `( p, Z P# K+ { delete p;% q. T6 ?# p3 y* |1 K7 T
return x;. ^: f9 Q6 W) C3 a8 \
}6 o9 `, `( L; y9 S0 Y
throw "空栈,不能执行出栈操作";
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9 l: }( W0 w5 `" r, H" _/ Mtemplate <class T>
, c$ S! k; D3 I, {8 V' E7 m4 C AT LinkedStack<T>::get()
' r2 T5 c. C' D: @" K" U# u, a{4 ^) }; u/ E; t9 q* F O4 q% x4 c
if(!isEmpty())
* `8 E' a- ?4 b" q {
$ ]* f7 P+ d8 f( @" J; x return top->data;
/ K: E) n0 u Z8 x }* T5 ^! E' I1 x
throw "空栈,不能获得栈顶元素";1 j5 Q0 Z% K( h4 x. Q5 H5 G
}& m5 C! j& y l/ T! T! i$ {1 q
3 i/ }& o' k& S$ a3 H% dchar * toPostfix(char *expstr)
1 S, x( V: l' s{
& `1 `; H. S: m8 R LinkedStack<char> stack;
. G5 l) ]; @, w \- Z4 j char *postfix = new char[strlen(expstr)*2];9 R. J" V9 ~6 t, K& ?
int i=0;
/ `7 {9 w& u2 @2 w* _ int j=0;
8 p8 Q7 _( `/ m! \ char out ;
, M/ Y' x$ \! P3 {. G6 ? while(expstr!='\0')
7 m2 L7 L0 b8 P: X8 ?9 z# [2 @ {
# C1 g3 ~$ _. U switch(expstr)
1 V l( X4 x" F" V: `2 q {
- g2 c* y$ o3 u0 F9 P case'+':) V/ O& n$ I# j3 y9 Y
case'-':
5 g- z8 s4 q! P% Y6 J% ~& F while(!stack.isEmpty()&&stack.get()!='(')0 d, }7 t9 m5 H# s! z6 Z
{' V Q; S4 X( ^7 @
postfix[j++] = stack.pop();* l3 N: L% W7 ?7 G
}7 `9 R* a" h8 m1 p* G
stack.push(expstr[i++]);
- A |; c# m. B$ b7 d7 P break;% a) }; R6 T+ q& F7 V% B1 Q" j
case'*':) Y2 j0 K* U1 @2 k }
case'/':$ A% ?! T! | d6 _: }
while(!stack.isEmpty()&&(stack.get()=='*'||stack.get()=='/'))
$ \* i9 _1 g7 y {
/ ]0 W( o7 O, N+ `+ x2 b# r1 c3 i0 M postfix[j++] = stack.pop();
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stack.push(expstr[i++]);
' b& i5 c- Y: P break;3 B: L( I: b4 x; t4 c' C2 k" o
case'(':stack.push(expstr[i++]);
$ H2 f& o \ A- f break;$ D. D+ d( k, Y7 @+ p, }
case')':out = stack.pop();
" y3 ~" ^# h m( K, ] while(!stack.isEmpty()&&out!='(')
. g5 u u: i* h- I2 M0 o {
9 z. M$ }9 @$ V8 `" b postfix[j++] = out;
7 j h, F6 ?; X; ]3 [ out = stack.pop();4 N+ k' r3 t) h1 J3 L0 P* Q
}5 i4 o) n$ c5 J$ l( ]
i++;
0 U @& Y. q, R {# D. F break;
4 M% K5 L8 J& Z/ E default:" t1 ~ X) N- v
while(expstr>='0'&&expstr<='9'&&expstr!='\0')
8 |! ^ i& j3 g$ E {
a2 G& A: w' Y A/ } postfix[j++] = expstr[i++];
2 x. x% ?! J9 p0 f }- Z# [9 F) P. Y$ B& c& h* s
postfix[j++]=' ';# U. {" |" z; ], X
break;
* s# X/ L! e6 s0 ?$ R2 e: G }- a: }7 d- k7 Z$ V: J
}4 A8 K( ~. n: W
while(!stack.isEmpty())
8 b: O7 R' p1 U0 U {* k5 z. U3 Q: i- U
postfix[j++]=stack.pop();
4 X5 v k$ U2 g% | }
1 ] w6 q1 c/ D. |; i postfix[j]='\0';9 F- g& l3 |/ }% }9 d2 y! V& c
return postfix;
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( ~: ~2 c6 }9 e( K& d0 H
int value(char *postfix)' y& f" n3 k& ^2 ?6 I6 @- t
{, y; u% O' |2 s0 U
LinkedStack<int> stack;
# I, U$ @8 r9 j int i=0;
0 d+ l! f. B; O5 a# H" k# _' V2 F int result = 0;2 ~; X7 G( [- {9 ~
while(postfix!='\0')
- L7 _$ {) U4 t& Q# E$ H4 B0 [ {! [; h( V* e. D5 z/ X
if(postfix>='0'&&postfix<='9')0 [8 @4 N3 s# M3 g; r, D
{; s: G- h; D5 z; r
result = 0;; x6 ~1 u" L8 u
while(postfix!=' ')
" l6 j* W6 w/ [) t; T {2 N6 E: i0 ? w t, v1 k
result = result*10+postfix[i++]-'0';
# P0 K$ b# ]9 v$ N }
8 C' F, Z' N! w i++;
2 h" f6 l: |% g6 C3 p! I stack.push(result);" J# O% S: ?0 C, o8 i
}
" q! a. s! V, b3 r: n" T* y6 H; Z7 j else
/ p1 n: W& q* \4 K {
6 r, u: m3 t2 y ?* P0 }( g if(postfix!=' ')5 R9 E" c+ H- Q- L" }
{
. |! r6 J+ z7 z) s/ C$ I8 k int y = stack.pop();
+ c/ W y+ D+ S% \4 a5 D int x = stack.pop();
* S4 L2 i' q$ J) E" @ switch(postfix)
, D' v0 |8 D' \* F* P/ U x) ] {
/ l8 @# n K6 x [( ] case'+':result = x + y;3 A: p1 h/ V. d
break;
: e7 v) b# J- R5 d( ^ case'-':result = x - y;3 }. ~0 n. L& P- {7 z% G
break;" p: ]% r4 c0 @& Y, d' H# {
case'*':result = x *y;
; \3 {. ~0 X! g2 o% z& A, c& |0 Z2 r, q break;; l3 D3 `' T& ]4 k1 p; }
case'/':result = x / y;
- x7 c/ t5 n3 U8 K break;' J. B2 O, T O6 m
}
6 `4 [! \6 x$ w/ ~9 C stack.push(result);
, T; L v$ N' D( R) }8 l }
/ i5 _$ M5 Q2 Z3 { i++;
, I4 I2 g' d! g- J$ T2 N; H/ S/ c }0 I5 h. r9 K$ g* x
}4 A: t) S; ?+ ]
return stack.pop();3 e6 v3 ?0 o% d4 l7 b
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' A; w& v* a8 pint main(): w; {, ?+ D7 F9 \) g5 \/ }
{
/ c h; ?9 I/ f3 M: _: l/ u //char *expstr = "121+10*(52-49+20)/((35-25)*2+10)";! Z9 q; e: n+ x8 f
cout << "请输入表达式:";7 e' ]( }. }( s: R9 a: R
//char *a ;
! E q E+ J$ H1 i. q //cin >> *a;
1 f" v: g9 m) W1 b char expstr[20]={0};* F. V9 J3 |- J( b7 b# d* _. Z! c
while(1)
. B2 x' a' e, q' n- R% | {
3 a+ s$ n4 K- X8 \4 Z cin>>expstr;
3 G% ]+ A* `$ Y% ?2 v" C. K char *postfix = toPostfix(expstr);9 d/ O( L" r; E
cout << "expstr= "<<expstr << endl;: K/ g: Y( Y% G
cout << "postfix= "<<postfix<<endl;7 ]. _" x" x- p% j+ f% D
cout << "value= "<<value(postfix) << endl;/ V0 Q" }: M3 _
}. g, ~; i9 } y, C3 Z- n7 T$ |8 \9 |
return 0;% v7 m% F0 ]: ?0 q. z2 ^, h% e
} |