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代入以下代码,得:11,9,4,2,1,6 滑稽~5 u2 }3 B% T1 M" S3 Z; ` _# d5 h" o
* o- M7 T3 C! a3 {# j#include <iostream>
' t* [# U9 S' G1 n1 ?6 [, a#include <string.h>+ ^2 J- g% _! p
using namespace std;* x6 K1 E& u1 V
template <class T>2 Q9 X, m( L, k$ d$ G8 I
class Node$ f' ?, k/ |: h$ ^: Y
{ a" H& u. O5 z d- E
public:( q% w5 q0 h4 k
T data;
" ~7 A0 x& S. T1 m: i+ [ Node<T> *next;
, Z$ r M, B. q5 [ Node()
0 b; _8 Z" b# j! ?" J% C" O {2 d# j9 y4 Y, ~$ Z% F% x# A
this->next = NULL;
6 f4 E d4 F& F2 O. ] }
. R2 v( R n% x Node(T data,Node<T> *next=NULL)3 _* A2 y9 m% k/ T& d' g; @0 s
{
/ G5 K8 b' S! d: t$ w this->data = data;6 I$ d( P- `: k1 b) C' r
this->next = next;& G8 k$ w# ?0 s% f2 a( Z
}. T; _) l# p; y r5 y+ I
};' ~+ x3 e. _7 H9 o1 W
% A, p0 b; A3 O8 A- utemplate <class T>
) v. ?" E3 I* h7 X" gclass LinkedStack/ L/ J: e+ ]- L$ D
{% {" F% S( d. g% b m. `! o) Q3 U
private: Q5 l: H, H7 Z+ [
Node<T> *top;
& d3 e3 ^1 H) o5 wpublic:
- Y6 p) G2 \( v0 P" x0 P. X LinkedStack();& h1 M. u. I8 E6 x7 R, }
~LinkedStack();3 p6 h# h0 I* [+ r9 [' A) C
bool isEmpty();# y0 g8 _! X& J7 L7 ^% ^2 x1 x
void push(T x);
7 H" s* Q q( e' V; ^ T pop();
$ `8 b0 E5 z- Q8 F0 o+ ?/ j0 I T get();
) c! e- }2 J; b3 R0 [% n) \ ^};
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template <class T>. R- ]; q+ p0 i! F
LinkedStack<T>::LinkedStack()
, A0 {: T& u& [{1 k, K* e) A) A5 J) I Z
top = NULL;
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: M6 t P4 z. w2 v6 s" Ctemplate <class T>
& x. j* T- J; q' M3 X6 d7 [LinkedStack<T>::~LinkedStack()1 P: r' O# `. i9 x' ?
{* _: Q( I9 q( _# {
Node<T> *p = top;+ U" ]/ r# N; E, b6 W& _* a7 R; U, O
Node<T> *q;
+ [, B8 I% c `& {: f while(p!=top)7 \ J# c) D! t, w* P
{
$ C! Z3 a' u; r. A% y, K q = p;
; N, \4 x) F7 {* L3 c p = p->next;
5 A; y: T7 i. f0 z/ g0 ~% C# A1 z delete p;6 I4 e9 t5 x- Y1 s; D' }
}" K! s2 o P$ { T
top = NULL;
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4 x: Q& L0 L9 n q9 Stemplate <class T>0 ^+ U0 U/ Z# U' {
bool LinkedStack<T>::isEmpty()4 `8 b0 s: y. r) ?( Y
{! a* |1 S4 B2 s" z* X/ {8 s
return top == NULL;' Q4 a% Z5 [7 `5 w
}
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template <class T>+ N) K$ U" A1 C
void LinkedStack<T>::push(T x)
! X1 z- P" y$ ^" _) v+ R( \{
: Y; Y# t5 |+ \/ Z; ^# v6 c9 l top = new Node<T>(x,top);, u" L Q' y4 ]7 r. D( w; V3 ?% h5 q* ~
}8 y% ?) n( G( b' L+ |' e% G @" n \
1 P" z5 a' o6 c* K! T/ ptemplate <class T>
: e' k" }2 p# vT LinkedStack<T>::pop()
7 a3 O5 w9 Y' I6 d8 f2 t{
6 A- X& f! f6 C* |# c if(!isEmpty()). Z, W$ e3 r/ @6 F& K
{' c+ ~) P) h& u7 ?! i
T x = top->data;
. a5 [5 h* ^0 ^$ |; i7 v) i1 t Node<T> *p = top;6 ^5 j1 g" x3 ?: H8 u
top = top->next;
+ N( F) `0 N1 ]* g' M* J* [ delete p;" u8 G9 y; }5 H
return x;
: k, l( J1 w; P+ I }
) p! p. t5 }+ C7 [0 }! } throw "空栈,不能执行出栈操作";) ^- d) \0 s; W5 i' S. G' y8 z/ k
}4 d' `! ^* F; o" C! n; }
7 g$ F6 q. c/ h$ a7 I' Ltemplate <class T>& \, M) Y0 [% J. i9 y- s2 R
T LinkedStack<T>::get()! z9 _& W, a# ]' @ h
{* q+ T J. t; z, W' a1 o: u
if(!isEmpty())1 b/ E3 w+ I* O; P% O) S! ?2 A
{
3 p2 E- y2 y Z2 o# y+ n; M return top->data;
/ }# i7 z3 v/ w/ F) r1 Z/ M. X* M }
( c; S3 m( a5 a throw "空栈,不能获得栈顶元素";% U6 S( V( m1 k& O0 o9 H4 F+ u
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char * toPostfix(char *expstr); u$ ^5 m5 W3 [5 r2 Y! s" P
{* j8 ?/ ?% C( E5 W, z7 Y
LinkedStack<char> stack;
2 q. i' A" B$ _. Z! @ char *postfix = new char[strlen(expstr)*2];
: U. B0 u4 z5 z) [1 m' p int i=0;
X1 t- Q/ K: ?! X; z: { int j=0;7 Y' r* v+ ?7 \ P' ~% a9 p
char out ;" V' |& Z& ^& G4 R
while(expstr!='\0')
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switch(expstr)2 h u: k9 J& |6 @1 a
{
8 }7 G- @! O6 Q( A! H case'+':
% _8 D; v) t% R" x' J7 X case'-':
0 W# ?/ T6 A/ U2 _ while(!stack.isEmpty()&&stack.get()!='(')% Q: N$ w: ?9 P) a
{7 w) E# q3 F- _0 v3 X
postfix[j++] = stack.pop();
( J; X+ v" k$ D/ {2 v) T }# r3 P+ G: G3 A
stack.push(expstr[i++]);" `' F" z5 I6 }2 V1 i7 l, }9 E
break;
]' {$ r. H, y0 f {% \* \7 U% e- x case'*':% z h) H& k- s, z7 }( m
case'/':/ W4 d9 Z3 ]" J U4 b$ P9 i n2 |
while(!stack.isEmpty()&&(stack.get()=='*'||stack.get()=='/'))1 B4 O/ ~, z5 [& ]* r, C
{# L3 {' J9 _ ~: E% ^, U! R+ ]% J
postfix[j++] = stack.pop();
6 m+ B/ o/ `% x5 Z }
* l+ H* ?) ^( p stack.push(expstr[i++]);
2 k+ F" M% S1 _2 t% p1 k break;
5 X6 ]% X8 ~$ m1 }$ q case'(':stack.push(expstr[i++]);
; I- t1 f W) m: h9 U6 `" e2 d break;# g- k0 ? K( O ]* U! j
case')':out = stack.pop();5 o4 s5 O/ c5 q/ i
while(!stack.isEmpty()&&out!='(')
, z7 b9 z4 X* u5 i( f5 Z) b) \% B {
4 N }) _5 ^3 i* U0 k. k$ _' Z postfix[j++] = out;( P- U) N* s3 H
out = stack.pop();' P: c* F1 a! j: F/ U
}# Y* Z, I |- I. A! A! s
i++;, P* B" N% v. q
break;
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while(expstr>='0'&&expstr<='9'&&expstr!='\0')
9 x& ~. |- ^9 z2 m( P2 T+ D {
7 x+ v8 m3 R8 V n* A/ B0 u) b postfix[j++] = expstr[i++];0 ]* }, @; ?" G z/ T# V7 U
}% Q" U3 q- C+ z+ E& P' y# B0 H
postfix[j++]=' ';
7 _! j6 ^! I" i) ^& _! _ Q% L break;; b( k+ ]# g t$ j3 }
}8 s! m1 q7 ]/ \( n
}6 h4 x0 ^# e3 u+ |* \
while(!stack.isEmpty())6 C! z% C, c3 C) @+ \4 ^- G
{
3 m: A' O3 H0 w postfix[j++]=stack.pop();. q4 z( H2 O. T9 Y6 v5 `% A
}( x3 ]5 Q: |. X0 }+ Z9 u# n. H' }7 ^
postfix[j]='\0';4 f2 L' g q! G9 M* G6 d
return postfix;& q4 X2 {& k7 g! [ [! N
}
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4 v. D" H8 e* V6 w# f* Jint value(char *postfix). j# p5 W4 L, \; S" L" n8 @
{0 d% u- \0 w1 V# s1 D
LinkedStack<int> stack;, L* ^* f8 x9 y o6 z# I- X
int i=0;
7 B, A" ?: O& F! P9 [ int result = 0;/ y6 f; h) }/ W1 ?8 I
while(postfix!='\0')
; S, e& v9 O7 n {
6 Q8 q0 | \* |/ t4 r" G1 } if(postfix>='0'&&postfix<='9')7 s0 E( X! f4 Y+ N
{
- H5 [3 @8 y }; g1 { result = 0;6 ~" \- b& r+ S4 l5 _* z
while(postfix!=' ')
2 m" Z6 m9 B3 u0 N {
& W4 K5 p) K" d9 A/ b( i3 X# }: A result = result*10+postfix[i++]-'0';$ z" \; P& Y7 N1 @% a
}
# T) D) v' }6 t6 y% A% z& e i++;
( U; Z4 \" d- `# k- ?/ T2 } stack.push(result);, \8 m( L1 J- @' v. |( X3 ^/ h0 ^
}
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{
+ R% C5 s7 |3 g! C' ~ if(postfix!=' ')- \9 i9 Z" z6 ~. Y0 o( @4 Z" g: O
{
+ G# ?2 t! @: n' e6 ? K5 a/ p int y = stack.pop();
: T7 m Q3 _" t( D- Y int x = stack.pop();% w: R R# n4 d1 ]
switch(postfix)
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case'+':result = x + y;$ L# x3 k ^6 L- J
break;
( E, \7 c: v* i, P case'-':result = x - y;5 ?, J6 H0 ]( n T! u9 Z1 G- F
break;9 h, s5 ]5 L! _3 V m. X$ ?% x( ?
case'*':result = x *y;# j9 d# [ N; i u) p% }
break;7 k# \1 e8 Y! ?- O U) l6 q( U& ]
case'/':result = x / y;
M8 X: V' T8 d break;
: ^) N( f$ k9 i9 d$ ] }
: I- U. Z" V9 `# W2 E" H stack.push(result);9 \! U Z" h& j0 x& a, B* R* x+ i @
}
. p0 k! Z' U5 p i++;
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return stack.pop();
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* U+ d2 {5 l2 {0 {2 w) u
int main()
% S3 l4 p3 ]9 g{
; r7 p: \0 A2 }: f //char *expstr = "121+10*(52-49+20)/((35-25)*2+10)";
?, q$ A6 J* N @ cout << "请输入表达式:";3 s" _2 z/ E$ y* Q- x/ g
//char *a ;' ~/ W2 X7 n+ n F" W, O# r! J& s
//cin >> *a;7 |( K m( k5 H# v4 M; r# t+ o6 z
char expstr[20]={0};" W. I. J& i m+ s! p: r
while(1)
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cin>>expstr;
2 [0 w! z" {) Z, d char *postfix = toPostfix(expstr);
/ V3 q/ _1 ~, r2 D1 w2 `% c cout << "expstr= "<<expstr << endl;$ ?5 H/ t6 o. b3 C5 f" [3 L3 {
cout << "postfix= "<<postfix<<endl;+ S# }- }' d5 D9 J% x$ k
cout << "value= "<<value(postfix) << endl;
- Z; j2 Y' [4 x" }; j. ^ }
r( G/ `7 i3 p7 D4 `- b! l- x return 0;
) t0 X% j2 ?" q% x. y} |