代入以下代码,得:11,9,4,2,1,6 滑稽~! T9 Q; I- a8 o
. j3 r m8 A" U& r. P* L#include <iostream>' x8 `. ~& d8 t( c; W
#include <string.h>) D6 ]# `+ Q3 D
using namespace std;
/ G3 m; h+ P- I- W" etemplate <class T>
, S% h8 p9 S ]class Node7 i( M1 g9 A- ]' U! ?8 y0 ?
{
6 K: S7 s8 ?# _public:
& V6 M8 a z. P# ^ T data;: \5 @% K' Z4 |( w
Node<T> *next;' w) y# z$ S) d- ?0 ]) t
Node()
4 I6 |6 q% b2 L# Z Y4 i& J {
7 ]: B- w! c: u* ?1 ? this->next = NULL;! q. ~- Z: s- x; @3 o* r5 I
}
- ^, {6 m$ \; A9 |) W Node(T data,Node<T> *next=NULL)( Y& L( d( ^0 O9 C! M7 p! q
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this->data = data;& t3 K! \ D" B0 Z2 e1 E) J8 u
this->next = next;
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};
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Q% x, a7 Z6 U5 [1 f$ Z3 gtemplate <class T>
: L: X9 ~' Y% u" g1 e, e oclass LinkedStack5 C, i2 g T1 b/ f6 y3 W, M
{
0 \8 `3 X' m% [6 `# i$ ` ?private:" Y/ C- h7 V4 p6 U
Node<T> *top;
9 I2 x) I+ c! {* l% T+ Upublic:6 U( {$ S( J% k* i% h+ z
LinkedStack();
' `5 W6 B" U; C/ i4 i8 i- t3 X* |; w4 ~ ~LinkedStack();
- l+ b) q+ ]7 Q bool isEmpty();
; s8 d0 B' x# L. f/ ~ void push(T x);" B) H9 s6 I( j6 x
T pop();
& D2 e" h9 p7 C6 t3 U T get();
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( m N; S2 I! btemplate <class T>
: u/ U8 r( ~, O$ B5 C/ MLinkedStack<T>::LinkedStack()
* y# B$ _, c) _& m0 t2 w8 Z* a{
' L9 w7 A; a3 L6 ]! m top = NULL;
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template <class T>; M1 U+ T7 \) p8 x) t- c
LinkedStack<T>::~LinkedStack()
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Node<T> *p = top;
7 T$ z7 Y2 \1 g {: v# H. _5 J' k5 f Node<T> *q;0 T. f- y$ R/ S/ Z% D
while(p!=top)- N# B: g. X- c$ s$ O6 O9 B& g/ R
{
- H& q" U+ P( A7 O3 g1 o/ B/ w q = p;
" x8 ^' x" F- w+ n! ` p = p->next;
6 y" F0 f% u, P, B5 n( i4 R; x delete p;' q5 a- [ O4 ]+ ]5 Z& U G5 ?
}
/ |: u+ w6 @) K$ o4 i5 g' b/ q" Y7 R top = NULL;
& z- f8 l8 _0 y0 F S}
Z* s5 q( C1 @; q
" z3 F% m6 b3 Stemplate <class T>
8 S+ g) X( r) y# S9 b. }bool LinkedStack<T>::isEmpty()5 q3 O- g, m1 A
{
; a% C6 Z6 I ^) e7 @ return top == NULL;
- i+ D# ~/ T. h' @6 a9 e}
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template <class T>5 d; N: f" N" I* E1 d
void LinkedStack<T>::push(T x)% [& z; V5 p% w! c. b$ ~
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top = new Node<T>(x,top);' U. }$ R* f' Q# `5 w9 H$ r% n; S
}
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* T+ g$ U0 N( z4 D6 C% utemplate <class T>- x, R' K3 l- Y' a+ E7 h P
T LinkedStack<T>::pop()( G+ u9 \, y% J
{% A6 k) C, N: @$ ]0 V, P
if(!isEmpty())
: k; [- e- C8 O0 W# K0 F) }5 Q {
/ F' h0 {% R) Y' C4 {/ o4 S( y T x = top->data;8 _% u+ C! x$ N, O e+ R K8 Q, e. Z/ H
Node<T> *p = top;
: C1 q# K5 Z5 v/ P4 [) H top = top->next;
' ^3 M, t- a9 k! k: ~& Y) A R delete p;! p. `, X/ x! k! w5 {3 X" C! W
return x;6 x& `4 D4 k- H+ ?
}8 _# C! {% l/ h: {
throw "空栈,不能执行出栈操作";
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4 a2 q B: E6 o) A8 F" b& d
template <class T>6 h8 N2 f. h7 F/ J
T LinkedStack<T>::get()
+ k7 Q) Q- p9 n5 h+ X3 `3 u9 o# f{
* {6 A, x9 \( G. S% L if(!isEmpty())
9 I4 O1 ?% }+ q1 S4 W+ N$ W0 X {
/ Z7 C% i& @) P/ \5 J+ a+ p6 p return top->data;" t' B3 j" E% N* u1 `) I
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throw "空栈,不能获得栈顶元素";& j' K5 R% K( o; D* l
}& E% h, a7 O/ ?6 B- N
$ j6 [/ l, t$ X$ T! y: ^$ ]* tchar * toPostfix(char *expstr)
4 C* L1 w0 c8 o9 ]2 z# k{
; n1 b- b; n4 G LinkedStack<char> stack;% N) o- P9 e, p1 W7 D3 }
char *postfix = new char[strlen(expstr)*2];
/ D9 j: |# h# |6 t/ ` int i=0;4 P7 H! C& n1 M5 Q9 y5 z
int j=0;5 N2 w+ }6 H" p! |' \" J. \: F, {
char out ;
- @% L: T1 d0 s: o' R# H) g while(expstr[i]!='\0')5 O' p3 _' a: z! s& ^! K
{
* F7 a# O$ v; s3 D: t switch(expstr[i])( T% {& U8 l S" W: {- Z4 t
{
) U# P' l2 r6 l9 S2 Y7 @ case'+':
/ O. }% y* H( z# w3 I L( Y case'-':
4 T5 x; s/ \* f& ]% T& I1 ^- p. W while(!stack.isEmpty()&&stack.get()!='(')
1 l% M4 B5 E: \ {
# {- j# X' [/ A& `% C postfix[j++] = stack.pop();, A" x; R# A4 h& v8 _* e$ r# ?
}
) m& j- z! v! P stack.push(expstr[i++]);
( u2 |2 l" I+ z% d" }3 F break;
% \1 R( [* r( X7 u$ R. {; |% D! r case'*':
6 [* D, E x/ ]- J1 b$ K case'/':: H( n6 L0 @5 ?7 c* u# L+ {
while(!stack.isEmpty()&&(stack.get()=='*'||stack.get()=='/'))# ^$ U! j. k @% D: m5 p" s& E& y
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postfix[j++] = stack.pop();
: e9 V$ p8 |9 g' T }
& }& b2 Z* Q+ G9 a stack.push(expstr[i++]);1 T* @ E. V' B/ k$ B
break;
1 ~+ C+ f) t) D/ y% y9 F3 q3 h8 Z case'(':stack.push(expstr[i++]);3 k$ k* E" K* ~; [% A6 ?
break;
; d# W$ h3 p/ l/ b case')':out = stack.pop();
2 c3 v* P( q- y# T& l: O while(!stack.isEmpty()&&out!='('). K, O! n! ]2 Z/ \+ n% z
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postfix[j++] = out;8 N# _8 p6 ?; D
out = stack.pop();
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i++;# l* }3 f4 Q' \0 K/ G$ J
break;
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while(expstr[i]>='0'&&expstr[i]<='9'&&expstr[i]!='\0')
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postfix[j++] = expstr[i++];
/ ]6 Z9 L0 T* t }
0 b0 p, }1 v' s8 K7 v# ^ postfix[j++]=' ';
$ X# p5 [* `% C" b/ h! W. N8 @2 R break;
& d2 z7 e+ w1 R( V9 v7 q6 ? n }
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while(!stack.isEmpty())
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postfix[j++]=stack.pop();
0 \5 P9 ^2 m6 T3 B; W5 P- @2 Y }
7 h) ]/ x: F6 j- j8 O- K% s5 p postfix[j]='\0';
) k9 o2 z8 \& S! A8 v return postfix;
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int value(char *postfix)$ j- S, x! S. u3 d8 I7 P
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LinkedStack<int> stack;
% N/ p/ {: M P1 t int i=0;) |7 d! p/ v( I1 K% o
int result = 0;
& l" {" [' Y# R while(postfix[i]!='\0')* G7 Y, a3 g) B, P7 V t
{; X& |- z& e( Y# n, z) Z& K3 O! V
if(postfix[i]>='0'&&postfix[i]<='9'): V9 j# M' T7 P# C0 k* U6 _* U W
{
: o# [' f. Y+ U1 I6 N6 K result = 0;9 s0 T) g) ?) w* z( n# Q
while(postfix[i]!=' ')4 X. T) M! M' T& V! H' M; \
{* Z; o- r- v# g
result = result*10+postfix[i++]-'0';
* }/ ?( ?+ a5 H, K/ r& F! m }
) x. q" u7 A6 Y* K# e9 |. T i++;
2 e& l2 H- X7 s; z* M/ B stack.push(result);4 _! E% X4 ~* x+ T
}
5 c8 L: y% l3 J else
, t# }7 o) j! C {
* W+ D: B/ L$ u if(postfix[i]!=' ')
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int y = stack.pop();
" T8 Y) u J& R9 G int x = stack.pop();
+ r! Q3 Q/ I, N* \! j: n8 N2 g switch(postfix[i])
) C1 p; ? Y* k, L+ t$ t {. I) s: F# l. G
case'+':result = x + y;# Z4 _8 w0 _& x6 ?* z& @! ~* t
break;
2 `' r" [9 O+ a case'-':result = x - y;! ~4 a( b% v4 H: X
break;
' \$ M: m% u- n# v2 e* s) f+ B m/ T case'*':result = x *y;4 W- ~& D. F' F7 R, e5 L
break;
4 e1 ^7 I, e6 J' w; J4 \4 B case'/':result = x / y;! t0 p# {% R% \2 ?6 s! u1 S
break;
4 N& v, p0 Y: g }
- `, y# t2 U" b3 ~+ t1 j6 `% {6 [ stack.push(result);
/ W1 [$ Q$ F# I! g) k }
( U6 n8 M% \2 g9 m2 M; c* p' H i++;
, y% t% h* v3 x( B) U }2 _1 x- i/ o! A9 P. z7 ]1 I
}
5 n6 X/ l% d# B- l- c" I5 X% l return stack.pop();: p/ u% W: b. H6 ]+ F7 F& _9 K
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# `& v5 W8 ?: i& i: M2 Z: ]4 w5 s( Yint main()* o- u1 O2 u% K: i1 t& S% |
{, n/ m& B9 n' i# Z
//char *expstr = "121+10*(52-49+20)/((35-25)*2+10)";8 w# w: Z, K+ H4 l
cout << "请输入表达式:"; T8 G7 _6 h0 ]& p% k: o2 g
//char *a ;- ^: Q; d( S5 U$ g+ J
//cin >> *a;
$ T% Y! l$ |: ~% | char expstr[20]={0};; K0 t* M" j3 X B$ w% A
while(1)
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cin>>expstr;) o3 W5 p8 A6 S+ P7 L) ]
char *postfix = toPostfix(expstr);
* w" Y1 y q5 l0 |8 d: p cout << "expstr= "<<expstr << endl;
0 Q; j6 U5 |4 x# M1 u r cout << "postfix= "<<postfix<<endl;: o) k$ o* F, Z! M
cout << "value= "<<value(postfix) << endl;
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return 0;
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