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代入以下代码,得:11,9,4,2,1,6 滑稽~2 Q* f+ n7 R7 r" a! N4 K8 V) \& E
8 y/ `% O9 a! Y) R5 \#include <iostream>& u2 o# w3 B/ _6 W* _
#include <string.h>
+ K I9 A4 V, o/ c7 e6 I' T! [using namespace std;0 |2 Y$ f% w* d+ T3 E, d
template <class T>
5 y1 N2 @4 y) a8 B) B+ B( vclass Node* ^$ U9 Y6 |- G* u7 R+ t' d
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public:# \4 }2 i( |6 k4 x5 ^
T data;" {$ Q, d0 y" p4 R2 T! O
Node<T> *next; `( c2 d/ x; M" U+ r! X! T
Node()! N- [& A. a" _) t. U
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this->next = NULL;1 [- ~$ D8 u' y6 Y
}
0 j0 b# G1 P, c; \* ]8 j; T Node(T data,Node<T> *next=NULL)
6 X; }! s: m |/ Z {
3 q. w) E8 Y. o this->data = data;
8 ]0 {* h" S4 ^8 q1 { this->next = next;3 ?- T: f! V Y: {
}
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4 b% @& b, ^+ Q% _8 ?# w0 Btemplate <class T>
( p2 [( t0 I, u# E0 M5 t1 sclass LinkedStack
& i7 e a5 \4 t* {( v{
5 x4 T; A. h J% F9 }private:
( j r, _1 w& A/ s1 F. V+ j Node<T> *top;; f0 o% B# P1 O6 p0 H! \4 M4 T8 G3 J
public:% D% q2 x: D" A, y9 ~" I
LinkedStack();
( a, l# ^! J6 m4 T ~LinkedStack();
$ _5 R7 E# O7 ^# \6 f bool isEmpty();
6 I9 ^% Z N( E void push(T x);
+ |) z, T, A' {7 M( E& H T pop();
3 z4 P. t9 K& n& b- p3 Y3 f- q T get();& u3 ]6 v g7 r; X- c+ ?* L
};! O8 g! [* D, ~! W' a6 p; u
4 n& ]6 A; A; I0 |! d1 Gtemplate <class T>
; L& R, Z/ ~- p" Q0 CLinkedStack<T>::LinkedStack()
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top = NULL;1 e+ i+ A: s$ r; V; j
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template <class T>
* |4 P5 A- k( L! `LinkedStack<T>::~LinkedStack()
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Node<T> *p = top;. A" `& b6 i; ]
Node<T> *q;
) v+ _$ }4 U H3 g2 X while(p!=top)
1 Q5 H8 Z7 L P: O {
5 q! z* Y: P6 K& i. h T; t$ s q = p;' I: k1 t% K* l6 G
p = p->next;
& A. d! l$ L2 _- G; x1 y1 E- \ delete p;
. \3 K q# [, S' F5 a/ D6 M }
9 |& j% v& p, |; r% c* o2 { top = NULL;" `3 |/ C3 h: h0 U: B5 Y* a
}
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template <class T>
3 L4 z4 [3 X: j2 W9 r& Rbool LinkedStack<T>::isEmpty()/ ?/ z* Q8 ]! n5 }
{
* q2 U! O/ w2 V6 o return top == NULL;% q5 h& E" U) H: B/ E: z- C) [6 }
}
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4 d. Z) z* x z; x' C* ~6 Itemplate <class T>+ P" t, [9 o4 S5 |9 x
void LinkedStack<T>::push(T x)
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top = new Node<T>(x,top);4 U+ Y B( ~* A, W
}
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4 O8 z) `- X8 k* ~" Mtemplate <class T>% P5 f' E! H/ ^
T LinkedStack<T>::pop(), \. G9 L$ [! V2 `+ S8 J* E H
{
' y; Z7 R$ @1 n& O) `5 N' L if(!isEmpty())
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T x = top->data;! s" ^4 ]: o% {; t
Node<T> *p = top;6 u+ d) B# k" m% r$ {& z
top = top->next;
: D2 Z: |1 r) j" T delete p;
' Y) J0 f6 T A" r return x;, \. D- ^& N: h
}
4 {4 k( c# k0 t; J. R- v0 x throw "空栈,不能执行出栈操作";
1 e4 O* q% L/ I( L}
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0 M9 T: ?% }# Q6 N9 T% J6 htemplate <class T>7 V. O5 P) \; I/ B0 C; j$ H
T LinkedStack<T>::get()
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if(!isEmpty())4 M% ]5 t: d% \6 r) i" z
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return top->data;
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throw "空栈,不能获得栈顶元素";( \3 l) i) T! ^' x) T0 \# R
}
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6 t" n8 v9 ^* Mchar * toPostfix(char *expstr)5 |7 M+ H: ?5 I& I4 |9 G- j7 L
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LinkedStack<char> stack;
# r$ R& p: d7 K' [& m5 ]- D5 \( | char *postfix = new char[strlen(expstr)*2];, @7 ~4 m2 ^1 E6 ~. b) L2 F2 j7 w
int i=0;' I/ w4 s, V& p
int j=0;
1 v2 J6 k+ g3 ]& P' ` char out ;% z/ G5 @! Y' j" E2 g
while(expstr!='\0')- i J3 Y$ ? \: c
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switch(expstr)7 U( p% c! w! `: c/ e
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case'+':! q0 L5 O6 V% R; p, ^* g
case'-':
?9 a; T0 v/ [4 ~ while(!stack.isEmpty()&&stack.get()!='(') O& U% |; ?7 D$ h" `0 a, i
{
6 q# B. G2 w) l- o) E% r* I postfix[j++] = stack.pop();/ @; H& N1 B2 J7 ~
}
; p( T* K" u, K# V7 b' [4 t stack.push(expstr[i++]);
$ }) h" l: d: S: {0 a: H break;
! Q( R$ n9 j8 p3 G case'*':
$ F7 O; g5 s" G2 R5 P$ }; E; G5 I case'/':
0 \/ [4 f6 e$ Y6 _ while(!stack.isEmpty()&&(stack.get()=='*'||stack.get()=='/'))
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postfix[j++] = stack.pop();
8 a5 B* ^3 |) u }
# R3 [/ e( A2 x0 X stack.push(expstr[i++]);# s9 Y" ?* k7 U, L9 [+ x
break;
* r% E, A- k- X: p+ V8 f case'(':stack.push(expstr[i++]);( x! s8 j* I0 C7 L* Q2 U
break;
) q" E' G2 `7 O* w+ A P case')':out = stack.pop();
% K3 i4 @$ k5 d( z1 x7 f while(!stack.isEmpty()&&out!='(')
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postfix[j++] = out;
- s. o8 x+ G( H out = stack.pop();4 S3 `- \8 a7 g
}
9 ^$ e6 ?; `& T2 s/ J i++;
, ^% a$ a3 u6 m, X& z L break;
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while(expstr>='0'&&expstr<='9'&&expstr!='\0')' e: r, @% W8 D4 U5 }% ^
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postfix[j++] = expstr[i++];
1 j' B6 W5 {- O4 Y0 K6 m! r6 w1 H }
2 R6 X' U$ K" } G. x5 A% X. ^ postfix[j++]=' ';
. V2 r2 c+ {: T# K {1 G' q2 G# M break;1 `/ n4 p" {9 ~1 {& n
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}
+ `/ ~0 S7 U+ e! d+ i% k# t while(!stack.isEmpty())
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postfix[j++]=stack.pop();
- `" C1 Q$ I! r% q m }
3 O, u4 }; X/ A1 s postfix[j]='\0';
( ~5 L# b* r- t2 } return postfix;. L/ [0 F% L! M0 `8 B2 \
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int value(char *postfix)
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& A, _$ j1 ]# N2 \' O: D LinkedStack<int> stack;- `; P) c4 e+ H1 T Y
int i=0;
4 u) P# w8 U7 ]: F: I- @+ \ int result = 0;
7 Y" ^; L* R7 O4 f while(postfix!='\0')
$ h, I# O. \1 X& ^2 g( z+ W1 e {
( ]1 r- {) j l' {9 q if(postfix>='0'&&postfix<='9')! _1 c+ G! I: ^3 G2 u/ E$ U! Y
{
3 @7 Z4 K$ Y1 ]5 `$ K% [3 } result = 0;
3 _( _ Y- ~. g2 m while(postfix!=' ')
3 B" G5 F: z0 f, Y9 s {
9 J) q G/ p- E result = result*10+postfix[i++]-'0';
% s8 ~2 }2 [6 s0 H' ?0 n3 m' o }
\3 ^& ~5 X" i i++;
3 u) `" h, H) G2 e0 e stack.push(result);
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else
6 w2 S: [' p6 U& ~$ o {
* L$ I! _+ c& k! `, s if(postfix!=' ')& ]! n' @( x$ |0 H
{
, l, U, I; g' N( E9 g$ S# D5 R1 e int y = stack.pop();8 t8 b1 f; A9 n/ P4 x+ G. S1 m$ ?, `1 F
int x = stack.pop();! h b2 j% O. c% i& ?" o
switch(postfix)
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case'+':result = x + y;/ Y( I. `( B% }( V# q
break;
7 F7 Q% }% m- a( C; J3 ] case'-':result = x - y;) R5 R N- y2 |% s3 t- d# o
break;& A0 J! @$ L3 k" G6 Y. j
case'*':result = x *y;5 c& z0 m0 l! a$ W; T6 T$ h
break;+ J9 q# ], H- N( V1 a1 ?- X, q
case'/':result = x / y;
0 [; g! b" _ d1 V) Q+ i- c break;
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stack.push(result);* v* B7 @3 Z5 U, b3 l: C
}
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}
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return stack.pop();0 ^$ X4 B9 p) w3 S: U+ \* ~( @
}
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! J2 ]" V/ J+ k' Iint main()
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4 ^+ A0 _, [5 j% X //char *expstr = "121+10*(52-49+20)/((35-25)*2+10)";' Z: ?, u6 y) }$ B) o& ]
cout << "请输入表达式:";+ ?2 \' g: R5 V+ h; R" s* C
//char *a ;0 l! x2 F* S5 {( H7 t
//cin >> *a;8 c6 E/ i6 T% v8 w" s% L' u3 A' t' X
char expstr[20]={0};$ w( B' S6 {/ w
while(1)9 P' U: ]; {( J. U7 Z0 s9 T3 h
{
/ h; _2 z; v, Z7 K( y: X( n cin>>expstr;
/ ^: Z3 H v( }5 f char *postfix = toPostfix(expstr);
z f, ]. ]$ c cout << "expstr= "<<expstr << endl;3 ]4 f( z/ {' i% ^) H
cout << "postfix= "<<postfix<<endl;
% D: v! z! o% [1 j( G# t# i cout << "value= "<<value(postfix) << endl;+ X4 R9 C+ m7 v2 S; F
}
! n$ S, o ?! @5 d% q return 0;
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