代入以下代码,得:11,9,4,2,1,6 滑稽~4 G' h8 u2 H% b
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#include <iostream>4 g( f' T5 D+ `: U( Z+ R! V2 I5 k# q
#include <string.h>) a5 e7 X8 A6 a# d3 H) Y$ w
using namespace std;0 W, G; W( q. d6 g5 x) D6 E. L
template <class T>4 n9 C3 S/ _3 J7 e
class Node [8 F! k5 F( w9 w9 e
{
& z) r' `+ b6 q- P- I- H7 I% `public:
3 s- N: ~3 I+ o T data;
) B' b" N$ c' I( x; K Node<T> *next;
( n: ~0 v, T& C; [4 D0 e* F0 W Node()# K6 _3 o! q9 l& z
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this->next = NULL;0 U1 z; w' @* h
}
4 R# W2 l0 G0 Y$ w" H3 y4 j Node(T data,Node<T> *next=NULL)
& {) T# |" m: H$ e! W, t# w {
( L R; t; L6 A( S: J# M this->data = data;
8 U; {) L) R, G: o this->next = next;
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};
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template <class T>
' H T8 j [1 ^6 x' U3 gclass LinkedStack; A7 a' e- ]+ P0 T
{( f" C0 E% ^3 j
private:
6 e9 n1 v- Z( T' i q1 S Node<T> *top;
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LinkedStack();
' k% K: J: g6 r* j; g t0 l ~LinkedStack();' J5 V. Y2 w, A) a
bool isEmpty();; z. L+ ^7 G }4 |
void push(T x);. s: V( e, i8 C' j8 `3 |: c# z# T+ j& a# Q
T pop();
$ u0 O- g3 z0 e( i4 h T get();
$ C; k" |( M" g1 Z};
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template <class T>! {/ G$ R% g" v. W$ H! E; C* C0 h4 K
LinkedStack<T>::LinkedStack()# Y+ K. F9 {: ]$ b9 q
{
* X( S: v1 e: V: D6 w top = NULL;. @: D, h( T& B3 o
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template <class T>
! G( ^& f3 \, x5 B. ?3 ]LinkedStack<T>::~LinkedStack()
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Node<T> *p = top;
0 H3 d$ O4 X6 b+ i Node<T> *q;
0 I% ]" c5 | | while(p!=top)4 [6 c3 y3 j% N$ t0 v0 x
{
* S+ n2 s6 J/ ]' a4 j9 B q = p;
5 C+ g! b. C3 g% Z) c! O p = p->next;
: B( m5 k5 g( m1 @, P: R delete p;$ F' H, L3 I# o0 M4 I4 \; d
}
9 p7 \1 R6 u) A% s; K top = NULL;
3 m2 B# A( S5 V5 e}
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5 D3 L5 N8 E z j- b: u8 s6 o& ]! Htemplate <class T>$ l Y. L1 b) h+ k( i% W
bool LinkedStack<T>::isEmpty()
# v; V+ [) i: c; K8 `* h, Y{
, ]: ?* t" `! H& n return top == NULL;
. Z( L4 a! M! }9 O+ F9 G; w9 d}
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template <class T>% P8 I+ c6 }8 U. f
void LinkedStack<T>::push(T x)2 o" j7 n: c7 @' s
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top = new Node<T>(x,top);- h9 K7 T! A1 I! x$ o' [
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template <class T> U. \# I2 Y4 ^6 B. m9 m6 P
T LinkedStack<T>::pop()
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if(!isEmpty())
1 Q9 X- J1 j" z) ?, Q* \ {
* ~8 z- G8 E/ `9 f T x = top->data;) k; i7 q- _1 D7 p9 f
Node<T> *p = top;4 e+ T+ ~$ Y; U; M: U
top = top->next;; F& _. Z% t7 V7 Q$ ]
delete p;
. T: u) l, ~0 ?, M) R# M& e1 u return x;
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throw "空栈,不能执行出栈操作";
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template <class T>
2 ^9 [; |. @- D# p9 U( KT LinkedStack<T>::get(); C4 n; J& T+ Z
{) U, [2 d' f8 `
if(!isEmpty())6 L% O2 R/ I4 s6 r! X' U1 E
{
* q) A: ~, H1 E+ } return top->data;
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throw "空栈,不能获得栈顶元素";2 ^/ A% t9 A+ f) g- J
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* s' A# o6 ], l9 Qchar * toPostfix(char *expstr)
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LinkedStack<char> stack;- ?' R u2 S& {" U9 @$ v
char *postfix = new char[strlen(expstr)*2];! b S5 F6 V( ^7 f3 |6 j! K h
int i=0;
, }# b& a3 K2 N B2 G) D" _; I int j=0;
- b$ J. T; l- L1 Y* a, @& C char out ; y8 B( C9 a! E7 Q: X5 I o. h9 G
while(expstr[i]!='\0')
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switch(expstr[i])
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case'+':3 B* G1 `% B" b
case'-':, n6 l* \6 `. L! n# l
while(!stack.isEmpty()&&stack.get()!='(')* _1 e' ]& Q' J6 F
{/ W& |/ P+ |" W4 K# [
postfix[j++] = stack.pop();% N& }2 I7 B; ^
}
+ z% K5 w+ Q4 U stack.push(expstr[i++]);) P- f3 e5 A5 \9 c `
break;
! j; K/ S1 ]& t6 M5 z3 E3 S case'*':8 i$ g5 [ [7 U
case'/':1 u: {* K9 { t- w
while(!stack.isEmpty()&&(stack.get()=='*'||stack.get()=='/'))! A3 E# g5 J0 ]) ]9 J3 c
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postfix[j++] = stack.pop();
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stack.push(expstr[i++]);( e/ r# t) E) f
break;
2 [0 l' [: V4 Q) ] case'(':stack.push(expstr[i++]);2 X7 T! X6 k# I
break;" v* e- E- ] \0 }6 a. |8 u7 _+ b7 w
case')':out = stack.pop();
- g) b$ p2 ^" Q7 r, t4 p q, s while(!stack.isEmpty()&&out!='(')
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postfix[j++] = out;8 D: t5 W4 X/ o3 I4 f
out = stack.pop();
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$ M4 E/ h6 \5 d# V2 ^ i++;! T8 G$ u* R5 w3 D! G9 O
break;( o/ S. d1 j0 p) T# m
default:. @; b1 p8 M& p
while(expstr[i]>='0'&&expstr[i]<='9'&&expstr[i]!='\0')
( w) {1 p' V/ E+ ~, s {
! g6 S4 M' r6 ]( U+ F8 b4 v postfix[j++] = expstr[i++];
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postfix[j++]=' ';
- G5 k3 j! k: F! ~6 ^: @ V- O break;
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: f8 | i! e9 d1 x* ?' Z }
6 S* Q5 s# ~: S/ o1 O while(!stack.isEmpty()) ]/ A) \5 E$ u
{
; K# ?9 G$ i% _% n postfix[j++]=stack.pop();7 l3 r9 Q0 X& x2 I! e
}/ {) ~+ R& c& v9 v5 Q/ u
postfix[j]='\0';
! X5 z9 V% p- j4 o0 x; Z1 k# j return postfix;7 Y I) ?! ^9 @( s
}
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int value(char *postfix)
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LinkedStack<int> stack;
+ ~ k+ V d8 ^$ k int i=0;1 u5 s7 u' C/ @) f6 P9 x4 J$ I
int result = 0;' k! d& h o- d+ k3 G) `' P
while(postfix[i]!='\0')
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if(postfix[i]>='0'&&postfix[i]<='9'). B! b! B6 z$ H
{
2 h2 h# ]" x% F8 ]* e6 a" T& ~' ? result = 0;
( v3 M; u% O! {4 S: f, U while(postfix[i]!=' ')
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result = result*10+postfix[i++]-'0';$ D+ W. m3 g/ M7 R5 p( _" x
}
$ z9 [! t6 b1 a) n i++;
4 N5 |2 H) p0 w1 N, {* [ stack.push(result);7 e1 y+ }9 ?7 f' Z$ d* I1 R3 U
}
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if(postfix[i]!=' ')
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int y = stack.pop();( v6 k3 N8 }$ J
int x = stack.pop();
3 D+ q5 V4 ` u4 M8 H3 S7 e* H switch(postfix[i])
( o' W6 [/ V1 |8 J$ n1 i8 i {
" y& n6 n& F& R3 s- T+ c2 V case'+':result = x + y;. ^8 b, P: W I
break;
* ^- T( J3 \) e$ ? case'-':result = x - y;
% [+ O6 U7 X2 j+ w7 ^: n( V break;
; q4 G$ N, u5 f* y% C1 S case'*':result = x *y;
: ]: ~. Y5 b) h/ l break;
" U7 p' s0 p: Z- [; r case'/':result = x / y;5 _+ k/ s. A( j
break;
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stack.push(result);
: @) \, g( \* B. I) ] }
4 Q% E- `; ^5 E! n- L i++;
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}
& N& O& c. ^# W$ Z- F9 I return stack.pop();
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int main()
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//char *expstr = "121+10*(52-49+20)/((35-25)*2+10)";
! w2 L. C4 {9 U/ S; |( a cout << "请输入表达式:";
1 M% O5 W7 c) G) C& c# G //char *a ;
0 W) X" ?: r. C //cin >> *a;
! u9 f5 w* F6 G- Y) I2 _ char expstr[20]={0};
7 g/ j8 ]. U8 f6 r5 ~+ a% P1 i4 Q' F while(1)
! s- |$ ]% j0 `7 _ {
" @- N: ?7 u* c# | cin>>expstr;
+ @/ W% f% K" I. l6 Z char *postfix = toPostfix(expstr);; @5 o2 v" N* M' x: ?% \% k
cout << "expstr= "<<expstr << endl;
( ~6 \# w7 l/ n' N* j9 o cout << "postfix= "<<postfix<<endl;
$ _( E9 Y* o. D W: `! ? cout << "value= "<<value(postfix) << endl;
. X" U: ?4 s9 K }
( C' a+ X. |" h: H* E return 0;6 L S6 o8 M, X1 E7 P3 T
} |